You are way oversimplifying things

1) You first need to obtain a merchant account in China

How?

2) Fraud Control

A new merchant account that repeatedly charges an oversea card in massive amount and you think the Chinese bank or Discover won't notice?

3) Chinese Tax and other Chinese regulations about foreign currency

If you do somehow get one, and is able to charge a huge sum to the account, without drawing attention from Discover or the Chinese bank, how are you going handle tax and other local regulations about foreign currency?

Further more, Discover can close your account at anytime if they don't like what you are doing.