Absolutely, Raoul, I have to completely agree with you:

I just can't think of ANY reasonable or attractive scenario that involves the need for using a recruiter.
I can think of lots of Invitations to the Blues that DO involve using a recruiter.
Don't use a recruiter. Just...don't. If you have to rely on one of those scammers to get a job, you really should reconsider coming to or being in China at all.

There are two basic important DON'Ts regarding teaching in China:

1. Do not come here on any other than a Z visa.
2. Never use a recruiter to find a job but contact schools directly instead.

There are also some important DOs regarding teaching in China:
1. Make sure you have a degree and a teaching qualification before looking for a job there. If you do not any of them, try to get them by studying for them before or while you are working.
2. Always ask for a written and signed/sealed contract to be sent to you prior to your departure for China. If they fail to send you that DO NOT GO!
3. As them for the proper documentation to be sent to you you will need to apply for a Z visa in your home country. If they fail to do so, DO NOT GO!

Personally, I have always been on a z visa or its equivalent to China ("equivalent" means that there were other visa categories in the period before China's open door policy back in the late 1970s and the early 1980s when I went there already). I also think it is a legitimate concern of the Chinese authorities to enforce age restrictions if this was an attempt to raise general standards in the crappy Chinese world of ESL (but enforcing age restrictions is not necessarily a major step towards better standards per se).

After many years of educational service in China, I am personally convinced that under the current system China is still too resistant to the necessary changes in its educational system and that because of this I would personally be wasting my time and energy over there. My alternative option has been to start a college project with many dedicated and honest collaborators in different nations, including Nepal, Korea, Singapore, Haiti, and various nations in Africa with Kenya as our main centre. After 5 years of quite successful operation, I can say that there is still a lot of work to do, and that there is still much, much room for improvement. Hence, personally I am not in the situation to look for another job. It's also a way to make sure that you do not become "jobless"...grin.