What the Chinese do is irrelevant. 

Just because a lot of speeding motorists are never caught doesn't make it okay for the rest of us to ignore the speed limit.  Similarly, just because some sellers ignore ebay's rules but aren't caught is no justification for the rest of us ignoring the rules.  If we all thought it's okay to break the rules just because someone else gets away with it, we'd end up with anarchy - and no buyers because they'd all be turned off.

I've read a lot in the forums about sellers being sick of buyers messing them around, but I get the distinct impression that a lot now think it's okay for sellers to mess buyers around by listing items they don't have in stock, or not to bother with an accurate description.