I'm not sure about China but I was in Japan a few months ago. Here are things I noticed that are different from western culture.

• They don't use CC and Debit cards for every transaction like here in US/Canada
• EVERYONE has a "train" card - which you buy/charge at the stations. You can use these cards at gas stations and some restaurants. These cards are different in each prefecture (states/provinces).

I could definitely see Japan benefiting from a decentralized currency