if you already have CNY on the exchange then arbitrage is possible.
Then arbitrage potential must be limited, because the loop is closed.
if you just walk in to the exchange with cash in hand, you can load up all you want.
if you have $100 million in dirty money in China you need to move, your lucky day has just ARRIVED
I was also wondering a good use for the Bitcoin ATMs... and this may be one of those good uses, no?