Also, I encountered a very oddball merchant today. Alldays (the convenience store). I tried using my Discover there and the cashier told me "no". Then I tried my SCB UnionPay card and they still said no. I asked "why" and she said that their acquirer has some problems passing the payment to the merchant for everything but BoC/ICBC/CCB so they'll only accept those banks' cards (they also said that corporate said that anyone that accepts one of the "others" will have the money docked from them personally if the payment doesn't come through after processing). The Baidu table says the acquirer no. 401xxxx is a credit union of some sort. Probably has something to do with it.

Point: UnionPay has some work to do.