As a Chinese that is studying in the US, I can give you some numbers.
About 80% of the Chinese are players that played Vanilla WoW originally and now have families/jobs, so they are mostly raidloggers that get online 2-3 days a week for 3hrs, which means, alot of them will buy gold. I don't know numbers, but probly 50% of them.
The rest 20%, are younger folks/people who dont have a regular job, and is making money by farming gold. They play considerably more every day and is the real gold farmers.
So its a misconception for people to think the majority of the Chinese are making a living to play this game. Lol no.