Hong Kong Consumer Council’s undercover test reveals that major chains including McCafé and 7CAFÉ often prepare drinks in disposable cups before pouring them into customers’ own reusable cups—undermining the entire point of bringing a reusable container.
The Consumer Council sent staff posing as ordinary customers to 20 chain stores—among them McCafé, Starbucks, 7‑Eleven, and Ah Yi Lemon Tea—between November and December 2024. They conducted 60 test purchases, asking about rules and discounts for using personal cups. The goal: assess how well Hong Kong’s food-and-beverage outlets support the city’s growing “plastic-free” culture.
BYO Cup Reality Check: McCafé and 7CAFÉ Fall Short
While all 20 chains accepted personal cups, the preparation process often contradicted their own green branding. In three visits to McCafé (two cold drinks, one hot), staff made the beverage in a disposable paper cup first, then poured it into the tester’s reusable cup. The same happened at 7CAFÉ, where an employee scooped ice from a plastic cup into the tester’s container before making the iced coffee. Such practices mean zero reduction in single-use waste.
Only 11 of the 20 chains offered any discount for BYO customers—typically HK$1 to HK$5 off. One coffee shop gave a 10% discount. But many stores failed to display these offers clearly, and branch-level enforcement was inconsistent; some staff members did not apply the correct discount at all. The Council urged retailers to improve staff training and signage to truly encourage consumers to change their habits.
Tumbler Test: Which Cups Keep Their Cool?
Alongside the store test, the Council evaluated 18 popular travel mugs (priced HK$80–HK$425) for heat retention, cold retention, leak resistance, capacity accuracy, and heavy‑metal safety.
Heat retention (6 hours) – Only two models kept water above 60°C: STANLEY (#15) at 63.8°C and NOC (#1) at 60.8°C. Starbucks, ZOJIRUSHI, and WOKY also performed well (50–57°C). Plastic models fared poorly, with water temperatures between 26.3°C and 29.0°C.
Cold retention (6 hours) – Eight cups kept chilled water below 11°C, including NOC, Starbucks, DECATHLON, and STANLEY. Again, plastic models lagged, reaching near room temperature.
Leak resistance – Twelve cups showed no leaks when inverted for an hour. Six others (including STANLEY and ZOJIRUSHI) leaked during inversion but passed a 45‑degree tilt test. Worryingly, the STANLEY mug—with its top‑heavy, narrow‑base design and large handle—tipped over on a 10‑degree slope, whether empty or full.
Capacity and safety – Five models (including MUJI, DECATHLON, and NATIONAL GEOGRAPHIC) had actual capacities more than 10% below their labelled volume, failing European standards. On heavy metals, trace levels of chromium, iron, and nickel were found in some stainless‑steel cups, but all remained within safe limits.
Consumer Tips for a Truly Green Takeaway
- Before you order: Check the store’s cup‑height limit (e.g., one 7‑Eleven caps at 15 cm). Ask if they prepare drinks directly in your cup.
- Ask for the discount: If the cashier doesn’t mention it, politely request the BYO offer.
- Choose your tumbler wisely: For hot drinks, pick a stainless‑steel model with verified heat retention (e.g., NOC or STANLEY). For leak‑free portability, look for cups that passed the inverted test.
- Avoid tipping hazards: The STANLEY mug’s instability on slopes is a real concern—consider a wider‑base design if you use a car cup holder or desk.
- Don’t over‑rely on labels: Actual capacity may be less than stated. Bring a cup that comfortably holds the size you usually buy.
The Council’s findings underscore a troubling gap between corporate sustainability pledges and on‑the‑ground practice. Consumers who make the effort to carry a reusable cup deserve a seamless experience—one that genuinely cuts waste, not just transfers it from a paper cup to a personal one. With better staff training and clearer in‑store communication, Hong Kong’s chains can turn their green slogans into real environmental impact.