Weird ... usually the Communist Party tries to prevent money from leaving China, not entering. (However the individual platforms such as Taobao gladly prevent everyone who doesn't have a Chinese ID from using their services, which is bizarre when you think about it.)
Yes and no... I live in Shenzhen and have an account on TaoBao and JD as a foreigner. And can buy with my own account and pay via WeChat or Alipay without problems too.
The difference is that i have a Mainland Mobile Number. And to get the account for that mobile number I needed to fill a document and provide them my passport to be scanned and added to the account details.
So it is by having the mobile number that my account works, since with the phone number I log in in Taobao, JD, Alibaba, Wechat and whatever more things I need in this country.
Have a medic appointment? Give them the Phone Number;
Membership card on the Supermarket? Phone Number;
Had you gone to the bank and didn't bring your Bank Card? No problem, give them the phone number...
You got the idea.