They have no trading fees, bots are most likely no stranger to them, therefore a much "bloated" volume if you will. You cannot compare them to Western exchanges with fees
but nobody seems to care. On top they have a fierce competition going on on the Chinese market right now:
http://btckan.com/priceSo weeks ago one of the smaller exchanges on that list reported a ludicrous volume at tiny order book depth, like 10 times Mt.Gox of that day and 3 or 4 times the volume of BTCChina. IThe thread is somewhere on this forum, I cant be bothered to find it right now. They all want to come out as the winner, becoming the BIGGEST Chinese exchange. Where else then at the one with best liquidity and lowest fees would you like to put your money? Its
likely they cook their order books to look better. Its like competitive bicycle driving, you know half the field is gonna dope so you have to take some enhancers as well to make it "fair play" again or get left behind. Why wouldnt they, after all there is no one checking on them.
Come to think of it, maybe this whole rally was fueled by Chinese ghost volume.