Worship Vietnam

One household runs three kinds of worship on the same calendar, each with its own recipient, altar and tray.

The census counts only Buddhists registered with the Sangha, which is why it shows about 5% Buddhist and 86% no religion; Pew's 2023 survey shows 38% Buddhist, 48% no religion, and the Sangha estimates about 60% of the population is culturally shaped by Buddhism (Pew practices chapter; Quản lý Nhà nước). The practical point for brands: the relevant population for offerings is every household, not the Buddhist third.

Frequency. Incense is daily or near-daily (96% burned incense for ancestors in the past year). Food and drink offerings follow mùng 1 and rằm (1st and 15th of the lunar month) each lunar month, death anniversaries (giỗ) for every deceased relative, and the festival calendar. Shops change the water and light incense on the Thần Tài (God of Wealth) altar morning and evening every day. A death triggers three rice offerings a day for 49 to 100 days, seven weekly rites, then one giỗ a year indefinitely (Luật Minh Khuê).

Region. The North is the most elaborate around Tết (Lunar New Year) and Ông Táo (live carp, paper robes, large cooked trays, green banana on the fruit tray) and keeps hungry-ghost offerings meatless. The Centre (Huế) is the most ritual-strict, with offerings on the 30th, 1st, 14th and 15th of every month. The South is commercial-deity heavy: daily Thần Tài (God of Wealth) offerings, roast pork and grilled snakehead on vía Thần Tài (God of Wealth Day), monthly outdoor offerings on the 2nd and 16th, and the giật cô hồn (grabbing the wandering-spirit offerings) custom where bystanders grab the offerings (Tạp chí Công Thương; Vietcetera). The Thần Tài cult itself is recent, roughly a decade old, and is spreading from South to North (Religious Studies Review, VASS).

Generation. Vietnam has the lowest religious switching (17%) and disaffiliation (4%) of the five East Asian societies Pew surveyed. Young urban households keep the rites but outsource the form: trays ordered online, prayers read from a phone, individual ready-made dishes instead of cooking. Participation is stable; the basket is changing. No survey quantifies Gen Z altar ownership or offering frequency; that is a gap.

One dominant peak (the Tết (Lunar New Year) complex, from Ông Táo (Kitchen Gods) through Rằm tháng Giêng (first full moon of the year)), a second peak in lunar month 7, a fortnightly baseline, and unscheduled life-event rites. Gregorian dates below are computed with the standard Vietnamese lunar algorithm (UTC+7); neither year has a leap month, and lunar month 12 has 29 days in both years, so there is no "30 Tết" in 2026 or 2027. Tết 2027 and Giỗ (death anniversary) Tổ 2026 are press-confirmed (Thư viện Pháp luật).

2026 mùng 1 / rằm (1st and 15th of the lunar month) dates: 17 Feb/3 Mar; 19 Mar/2 Apr; 17 Apr/1 May; 17 May/31 May; 15 Jun/29 Jun; 14 Jul/28 Jul; 13 Aug/27 Aug; 11 Sep/25 Sep; 10 Oct/24 Oct; 9 Nov/23 Nov; 9 Dec/23 Dec; 8 Jan 2027/22 Jan 2027. 2027: 6 Feb/20 Feb; 8 Mar/22 Mar; 7 Apr/21 Apr; 6 May/20 May; 5 Jun/19 Jun; 4 Jul/18 Jul; 2 Aug/16 Aug; 1 Sep/15 Sep; 30 Sep/14 Oct; 29 Oct/12 Nov; 28 Nov/12 Dec; 28 Dec/11 Jan 2028.

Three more dated occasions matter for specific categories. Tết Hàn Thực (3/3 lunar: Sun 19 Apr 2026, Fri 9 Apr 2027) turns bánh trôi and bánh chay (glutinous rice balls) into the day's defining purchase, mainly in the North (VietnamPlus). Phật Đản (Buddha's Birthday) / Vesak (15/4 lunar: Sun 31 May 2026, Thu 20 May 2027) is a pagoda and vegetarian occasion with flowers, water, fruit and charitable meals; vegetarian sets sell online and at markets (vietnam.vn). Trung Thu (Mid-Autumn Festival) is the one occasion with a packaged product at its centre: mooncakes are mandatory on the tray and are also the gift, so Kinh Đô, Orion, Phúc Long and bakeries compete on box architecture and price tiers every year (VnExpress; VietnamNet). Scheduled vegetarian days go beyond the 1st and 15th for stricter households: 2, 4, 6 or 10 days a month (nhị trai, tứ trai, lục trai, thập trai), and some keep the whole of lunar months 1, 4 and 7 (Luật Minh Khuê).

Life-event rites run all year and share one shopping basket: khai trương (opening), cúng xe (new vehicle, then monthly), động thổ (ground-breaking), nhập trạch (moving in), đầy tháng (baby's first month) and thôi nôi (baby at one month and one year: 12 small xôi and chè plus one large), weddings (tea, liquor, betel, bánh cốm, bánh phu thê at the altar), and deaths. The business template is the same every time: five fruits, 3 xôi, 3 chè, 3 cups water, tea, liquor, betel, rice, salt, candles, incense, votive paper, sweets, and roast pork or boiled chicken by means (Di Động Việt). The weekday matters: when Ông Táo (Kitchen Gods) 2026 fell midweek, Hanoi families shopped the Friday before (VnBusiness).

The altar has a gradient of permissiveness. What qualifies depends on who the recipient is.

Purity and wholeness are the eligibility rules. Offerings must be fresh, new, untasted and unused: "đồ tươi, mới và đầy đủ" (fresh, new and complete), arranged symmetrically in odd numbers (Sapo). The rooster is whole with its head toward the incense bowl; eggs in thịt kho tàu stay whole; the snakehead is grilled unscaled with fins and tail intact. For a packaged product this means sealed, undamaged, label out. A dented can or crushed box fails twice: it breaks the "đầy đủ" rule and ruins a glued, label-out tower.

The five-fruit tray (mâm ngũ quả) flips by region on name puns. North: green banana hand at the base holding a pomelo or Buddha's hand, with persimmon, mandarin, kumquat and red chilli for the five-element colours. South: custard apple, fig, coconut, papaya, mango ("cầu sung vừa đủ xài", pray for enough to spend) on a pineapple base with a pair of watermelons; banana (chúi, to sink), orange and mandarin (quýt làm cam chịu, taking the blame), pear (lê lết, dragging), apple (bom, bomb) and durian (sầu, sorrow) stay off. Centre: no fixed list, whatever is fresh and local (Tạp chí Công Thương; Vinpearl). Everywhere: just ripe, firm, unbruised, unwashed, stem on, no thorns, no strong smell, nothing artificial. The Southern banana ban applies to the Tết (Lunar New Year) ancestral tray only; a ripe banana hand sits on Southern Thần Tài (God of Wealth) altars every day.

The three cups. Water is the one non-negotiable cup on every altar (folk belief holds that spirits drink plain water). Tea and white rice liquor are the traditional companions, in sets of 3 (two outer for ancestors, middle for deities) or 5. Beer and soft drinks are additive, never substitutes, and guides describe can towers on the altar as "không phải phong tục truyền thống" (not a traditional custom) but now accepted as a wish for abundance that doubles as guest stock (FPT Shop; Ngôi Sao).

Thụ lộc (consuming the blessing). Cooked food sits 15–30 minutes or one incense cycle, then the family eats it; "không hề lãng phí" (nothing is wasted). Tết (Lunar New Year) towers sit for days and are opened for guests. So altar goods must be good to eat, portionable across a household, and shelf-stable through the display. The one exception is the hungry-ghost tray, which is the opposite brief: cheap, many small units, outdoor-safe, acceptable to strangers.

Pack rules that practitioners describe (consultant and trade observations, not survey-backed, so treat as hypotheses to check in review data):

Square and upright. Rigid boxes with sharp corners that stand on a small altar or stack into a tower win; floppy bags read as messy and are opened and plated instead.

Colour. Red and gold for Tết (Lunar New Year), Thần Tài (God of Wealth) and auspicious rites; yellow, lotus pink and green for Buddha altars and Vu Lan (Buddhist filial-piety day); stark white, black and dark blue or purple primary packs are associated with mourning and avoided for altar use.

Portions. Individually wrapped pieces inside the rigid box, because the tray stays out on the living-room table for days in a humid climate.

Size. Apartment altars (bàn thờ chung cư) are compact wall shelves under a smoke shield; tall bottles and oversized hampers do not fit, and 250–350 ml bottles sit better than 500 ml next to a small incense bowl.

Counts. Odd numbers (1, 3, 5, 9) for anything visible on the altar; 12 for hungry-ghost and baby rites.

The savoury tray carries a small bowl of pure fish sauce with chilli at its centre, which is why "first-press" purity language in fish sauce overlaps with the idea of offering the purest ingredient.

Two proverbs frame tone: "Phi tửu bất thành lễ" (no liquor, no rite) explains why a drink is always present; "Lễ bạc lòng thành" (a humble offering with a sincere heart) is the consumer's own defence against showy or guilt-driven buying.

Votive paper and incense. 73% offered votive money or goods in the past year (Pew). The Buddhist Sangha asked temples to stop burning votive paper in 2018 and Decree 38/2021 fines burning in undesignated festival places; Hàng Mã vendors report revenue about half of pre-2019 levels and HCMC markets say "càng lúc càng vắng khách". Household burning continues, more in the North and provinces than in HCMC. Incense is a loyalty purchase (light, natural scent, no chemical smell) (Báo Văn Hóa; Tiền Phong).

The same four logics recur in every category: whole and sealed; red or gold and stackable; a modern layer on top of a fixed ritual core (incense, water, flowers, fruit, rice and salt, liquor, tea); and eaten afterwards as lộc, except for hungry-ghost goods.

Notes by category.

Fruit is the one category where region decides eligibility, and supermarkets are winning altar share on traceability rather than price: a Hanoi shopper paid more for VietGAP-stamped longan "because it carries a traceability stamp" (Tạp chí Công Thương).

Confectionery is the most altar-ready packaged category. Shopee's own Tết (Lunar New Year) guide describes the small Danisa tin as "vừa đủ trưng ở các khu vực thờ cúng có diện tích hẹp" and Cosy as "phù hợp trưng bày trên bàn thờ" (Shopee Blog). Thần Tài (God of Wealth) day confectionery is shaped as money bags and gold ingots in yellow and red, and sellers compete on being "đóng thành lễ thuận tiện", packaged as a ready-to-offer set (VnBusiness).

Beer and soft drinks reach the altar through the tower. The instruction is "chọn đồng nhất thương hiệu" (one brand) and "mặt có chữ hướng ra ngoài" (label out), which makes the brand face the decoration (Shopee Blog tháp nước ngọt). Traditional lists for ancestors, Ông Táo (Kitchen Gods) and openings specify 3 cups of rượu, not beer; beer appears only in Thần Tài (God of Wealth) and modern lists.

Coffee and cigarettes are the daily Thần Tài (God of Wealth) offering and no brand owns the moment; guides describe the cigarette as a whole pack with two sticks poking out (Luật Minh Khuê).

Pack format splits three ways: altar (small single units in ritual counts, uniform, unopened), gifting (tins, boxes, baskets assembled to order, practicality now ahead of show), consumption (24-can cartons and bulk). Kantar ranks biscuits, beer, carbonated drinks, cooking oil and sugar/MSG as the top five gifted FMCG categories at Tết (Brands Vietnam / Kantar).

Failure modes documented: hidden or past expiry in baskets (sellers "quay mặt in hạn sử dụng vào trong", turn the date inward), empty boxes padding baskets, bruised or dented fruit, counterfeit Danisa tins without the inner foil, wilted or chemical-smelling items, and anything showy or cluttered that reads as disrespect (Báo Pháp Luật; Mytour). Because altar leftovers are eaten by children and elders, expiry is a safety complaint, not a cosmetic one.

Consumer vocabulary to mine in review data: để cúng, mua cúng, cúng xong ăn, trưng/chưng bàn thờ, chưng Tết (Lunar New Year), để thờ, trang trọng, trang nghiêm, sang trọng, bắt mắt, đầy đủ, nguyên hộp, nguyên seal, đủ lon, lon móp, hộp móp, cận date, hết hạn, màu đỏ đẹp, tài lộc, thụ lộc, trọn gói, tận nơi. Marketplace review bodies could not be retrieved for this report; these terms come from press and retailer editorial and need checking against actual review language.

Occasion by category fit. H = central or commonly documented; M = plausible or observed depending on household; L = peripheral; — = outside the rite.

Beer is not an offering on any altar and is left out of this matrix. Every traditional tray list specifies rượu trắng (three or five small cups), the Buddha altar bars alcohol, and beer appears only as a Tết (Lunar New Year) decoration placed beside the altar and as an optional extra in a few modern Thần Tài (God of Wealth) lists. Its real role is hosting at giỗ (death anniversary) and Tết. Soft drinks are scored low for the same reason: an add-on by family habit, never a required item.

Mooncakes deserve their own line. They are the one packaged product that is simultaneously the offering, the gift and the shared snack, with Kinh Đô citing a Worldpanel most-chosen result for 2025 and prices rising in 2026 (VnExpress); roadside traditional stalls are losing ground to corporate gifting and e-commerce (VnExpress).

Vegetarian is also a measurable market: Vietnam's vegetarian food market is reported growing about 8.1% a year toward roughly US$220 million by 2033 (IMARC via VTV), with 15–20% peak lifts on Vu Lan (Buddhist filial-piety day), Phật Đản (Buddha's Birthday) and the 1st and 15th, and Co.opmart raising vegetarian stock about 20% for peaks (VTV; vietnam.vn). A "chay mặn đều dùng được" (usable for both vegetarian and non-vegetarian cooking) claim on seasonings, sauces and noodles is the practical bridge between the two trays in one household; it is a practitioner suggestion rather than a documented consumer demand.

Incense is the one ritual category with branded, differentiated products (herbal lines built on cinnamon, ginger, bồ kết and agarwood, e.g. Vinacay), and Vietnam is a major incense producer and exporter; brand penetration among worship buyers is not measured (Vinacay).

Channel follows the item. Fresh altar goods (fruit, flowers, boiled chicken, betel and areca) and votive paper are still bought at wet markets and street vendors, where vendors know the ritual (Hanoi's Chợ Hàng Bè sells boiled chicken with a rose in its beak for mùng 1 and rằm (1st and 15th of the lunar month)). Shelf-stable goods that double as altar items and gifts have moved to supermarkets, minimarkets and e-commerce: 70% of Tết (Lunar New Year) shoppers used supermarkets and 31% wet markets in 2023 (Cimigo via B-Company); 63% say they prioritise e-commerce for Tết 2026, up from 48% in 2024, and Gen Z and Gen Y are the majority of Tết shoppers on Shopee (VnEconomy; VietnamNet). Ready-made trays come from specialist services, restaurants and supermarket pre-orders; no food-app evidence was found. WinMart+ put about 80% of its 764 new 2025 stores in rural areas and reports imported fruit growing there (VnExpress).

Timing runs on two rhythms. Tết (Lunar New Year) is a long ramp: FMCG spend roughly doubles a normal month and peaks about two weeks before Tết; gift baskets peak two to four weeks out; e-commerce peaks 7–10 days out; corporate basket orders run early December to 20 January, family orders from mid lunar December; cooked altar dishes sell out on 27–28 Tết; Co.opmart tray pre-orders close around 22 Chạp for delivery on 29 Tết (Kantar Worldpanel; Metric via Brands Vietnam). Monthly worship is a 24–48 hour spike: votive paper and chicken orders on the 13th–14th, fresh flowers, fruit and chicken before dawn on the day; vendors slaughter from 5 a.m. so shoppers can light incense before work (Tiền Phong). Rằm tháng Bảy (seventh-month full moon) fruit runs about 3x normal from the 9th, votive paper 2–3x from the 12th, vegetarian eateries 2–3x for the month.

Gift sets and the altar are the same SKU set. Saigon Co.op builds its 99,000–199,000 VND own-label baskets explicitly "from altar offerings and family meals": tea, ST25 rice, noodles, seasonings (Tuổi Trẻ). The 300,000–500,000 VND band dominates in 2026; baskets under 500,000 outsell premium; 77% of households received FMCG gifts last Tết (Lunar New Year) with penetration declining; gifting is shifting to practical and health items, and shoppers prefer to pick items and have them packed rather than buy pre-assembled baskets. The custom of placing a received basket on the altar before opening it is widely assumed but was not documented in any source reached.

Who decides. A woman is the "tổng chỉ huy" of Tết (Lunar New Year) shopping in 68% of urban households; elders set what is ritually correct; younger members order online (VnEconomy). 56% will buy at least one ready-made traditional food. Young people are reported offering bubble tea and fried chicken to Ông Địa (Earth God) on the logic that offerings should match what the person eats (Vietcetera).

"Worship lite" is uneven. Votive paper and alcohol are shrinking (clearer in HCMC and at pagodas since the 2018 Sangha letter); fruit, flowers, incense, tea and ready-made food are stable or growing. The 2026 middle path is buying individual ready-made dishes (xôi, chè, giò, vegetarian dumplings) to assemble one's own tray rather than a full tray; Ông Táo (Kitchen Gods) 2026 feast orders were flat while individual-dish purchases rose (VnBusiness).

Ready-made tray services (Đồ Cúng Việt, Đồ Cúng Tâm Linh, Tâm Phúc, Tâm An and others) are HCMC-centred, built on life events (đầy tháng, thôi nôi (baby's first birthday), khai trương (business opening), động thổ (ground-breaking), nhập trạch (housewarming), new car, month 7), ordered by hotline, website and Facebook, delivered free within 30 km, and bundle wine, rice, tea, soft drinks, incense and candles (Toplist). Supermarket trays go back to at least 2006 in HCMC. Users are defined by time scarcity and small households rather than income. Full trays run roughly 260,000 to 1.8 million VND depending on occasion (context only).

Brands circle the altar with codes and let shoppers make the connection. Across 20+ campaign sources from 2019 to 2026, no mainstream brand uses "cúng", "bàn thờ" or "để cúng" in its public marketing. The explicit altar layer belongs to retailers, tray services and small online sellers.

Sources for the table: Brands Vietnam on Coca-Cola's swallow; Diễn đàn Doanh nghiệp on Kinh Đô Lộc 2026; SGGP on Orion Tết An; VietNamNet on Bia Saigon Gold; Brands Vietnam on Ensure Gold Vu Lan; Brands Vietnam on Nguyên Xuân; VnBusiness on PNJ; Thương hiệu & Công luận on supermarket offering lines; VnExpress on frozen trays. Campaign results are brand- or agency-claimed unless stated.

The codes are moving. Reunion (đoàn viên, sum vầy) is still the default theme but social discussion of it fell from 36.6 million to 8.2 million mentions, and 2024–2026 campaigns pivot to "an" (peace), "đủ" (enough), "tri ân" (gratitude) and "hứng khởi" (uplift) as Gen Z redefines a good Tết (Lunar New Year) as "đủ" rather than "to" (Brands Vietnam BuzzSpeak; Brands Vietnam Tết 2026 round-up). Red, gold, swallow and blossom now run across biscuits, soft drinks, shampoo and coffee cups and no longer differentiate; differentiation in 2025–2026 came from mechanics (personalised wishes, gold caps, scratch codes, AI films).

The risk envelope is regulatory rather than religious. Coca-Cola's "Mở lon Việt Nam" (2019) was ruled a breach of the Advertising Law's fine-customs clause and replaced within days; Huda heritage billboards were pulled on the same clause. The Sangha's 2018 letter and 2019 circular target votive paper at temples, and the Sangha's accepted brand route is charity and gifts, as the Nguyên Xuân partnership shows (Nhà Đầu Tư). Tết (Lunar New Year) is roughly 20% of annual FMCG revenue and higher in confectionery and beer (Việt Nam News).

Photographic evidence of brands on altars exists but is anecdotal. A 2026 VietnamPlus feature on Tết (Lunar New Year) ancestor worship shows red Coca-Cola cans on a household altar beside the fruit tray (VietnamPlus); a Vietnam Beverage Association piece on drinks in Tết culture pictures Fanta, Trúc Bạch and Bia Saigon, G7 coffee and other packaged drinks in a festive altar scene (VBA). These are single instances, not penetration data. Coca-Cola's own 2026 Tết launch material describes swallow, blossom and prosperity motifs and never mentions the altar (Coca-Cola Vietnam). Claims in consultant reports that beer and cola brands include tower-building kits inside festive cartons, and that altar bundles are sold through GrabMart or ShopeeFood, were not confirmed by any source in this research.

These are observations from the evidence, stated so a category team can decide what to do with them.

Worship is a near-universal, calendar-fixed demand driver that no FMCG brand currently addresses by name. 95% of homes, 86% offering food or drink yearly, a fortnightly rhythm, and two annual peaks on dates known years ahead. The altar vocabulary is owned by retailers and tray services.

The planning calendar is lunar with a solar overlay. Tết (Lunar New Year) packaged-goods demand builds four to six weeks out and peaks two weeks out; corporate baskets are decided three to four months ahead with retailers; monthly worship compresses into 24–48 hours around the 1st and 15th, with pre-dawn availability of fresh items the constraint. The weekday a lunar date falls on moves the shopping day.

Two opposite worship shopping modes exist and should not be conflated. Ancestral, Thần Tài (God of Wealth) and Tết (Lunar New Year) purchases premiumise (brand-up, tins, imports for "guaranteed quality", ritual counts, label-out display). Hungry-ghost purchases economise for volume (cheap, many small units, outdoor, given away, never brought indoors).

Confectionery and biscuits are the most altar-ready packaged category: a standing line item on every tray list, tin formats described by retailers as suited to small worship spaces, individually wrapped pieces for sharing afterwards, and the top gifted category at Tết (Lunar New Year). Counterfeit anxiety (Danisa) shows that brand trust is part of altar eligibility.

Beer and soft drinks are Tết (Lunar New Year) hosting and gifting categories, not worship offerings; they reach the altar only as consumer-built Tết towers placed beside it, which reward one brand, 9–11 units, 330ml cans and red or gold liveries, and the brand face is the decoration. The 6-pack is weak for drinking but is the base tier of a tower. Beer on the ancestral altar is accepted as modern, not traditional; traditional lists specify three cups of rice liquor. A bowl of plain water must always be present regardless.

The Thần Tài (God of Wealth) altar is the most consumer-goods-friendly and the most frequent: refreshed twice a day in every shop, with coffee, cigarettes, bananas, candy, beer and soft drinks standard rather than tolerated, and lộc consumed by owner and staff only. No coffee or confectionery brand is attached to it, and the cult is spreading from South to North.

Oil, fish sauce, seasonings, milk and instant noodles have a gifting and charity role, not an altar role. Oil carries a lucky pun (dầu / giàu) in the South; sugar, rice and salt are on every tray. Instant noodles on hungry-ghost trays are widely assumed but did not appear in any of about ten tray guides retrieved; treat as unconfirmed.

Fruit eligibility is decided by region and by name, and supermarkets are winning altar fruit on traceability rather than price. Imported apples and pears pass in the North and fail in the South.

Vegetarian is the growth edge of the ritual basket. Buddha and Vu Lan (Buddhist filial-piety day) trays are strictly vegetarian; tray makers see 8–10x normal orders in month 7; retailers widen vegetarian ranges by about 20%; Hanoi buyers prefer natural ingredients while HCMC buyers crowd mock-meat. Vissan is the only confirmed branded vegetarian Vu Lan launch found.

Votive paper and alcohol are the shrinking parts of the basket; fruit, flowers, incense, tea and ready-made food are stable or growing; buying individual ready-made dishes to self-assemble a tray is the 2026 middle path and favours branded components over full-tray services.

The gift basket and the altar tray are the same SKU set, and retailers already design entry-tier baskets from altar items. Gifting is shifting to practical and health items under 500,000 VND; the custom of placing a received gift on the altar before opening is assumed but undocumented.

Codes that still carry: an (peace), đủ (enough), tri ân (gratitude), lộc (blessing), hiếu (filial piety, nearly unused at Tết (Lunar New Year) and the most direct unclaimed bridge to the altar). Red, gold, swallow and blossom are now table stakes. The compliance line is the Advertising Law's fine-customs clause, not religious objection; the Sangha's sanctioned route into worship spaces is charity and gifts.

Two further observations from the consolidated reports, both practitioner-level rather than survey-backed: compact formats fit the apartment altar that young urban households now keep, so pack height and footprint are part of altar eligibility; and families report a post-ritual burden of sugary cakes and sodas accumulated from the altar, which is one reason gifting has moved toward tea, nuts, low-sugar biscuits and health items.

Gaps this report could not close: no survey of how many households offer every mùng 1 and rằm (1st and 15th of the lunar month); no Gen Z altar-ownership figure; no retailer disclosure of monthly rằm (full moon, 15th of the lunar month) fruit and flower uplift; no brand-association data for "để cúng"; no marketplace review text retrieved (terms listed above need checking against actual reviews); no documented brand–tray-service partnership; Central Vietnam thinly covered on shopping behaviour.