Agents like recruiters and private schools are in it for the money. If you're not able to perform and help make them that money then you'll be fired. You'd be naive to think otherwise.

As for China, the culture allows for foreigners to work with visas as long as they're not expired. I've done it too, no prob, are you a man or a mouse?

So are you suggesting I can get a transit visa and work in a summer camp for a week and that'd all be above board? That's ridiculous!

As for your final comment. If by that you mean you've got to have balls, guts, etc. to work illegally in china (or any country) then I'd agree but You'd also have to be lacking a large amount of sense.