I agree the Chinese exchanges don't have the coins they claim. The issue is does that result in the price recovering, as they buy to try and cover the claims on them or a total collapse as everyone loses faith in bitcoin.
I don't think they are fractional reserve, just high frequency.
Example, draw a line across a table, one side of line is exchange, the other side is you, tape a 1 BTC wallet to the rim of a bicycle wheel, $250 on the other side, now spin it at 500 RPM.... congrats, you just created 30,000 BTC an hour volume. If measured by the forex standard of a buy counting as 1 and a sell counting, each buy/sell pair counting as 2, you've got 60,000 BTC volume.
I like your volume illustration, and they are certainly high frequency, I just don't see those two things as being mutually exclusive.
If the Chinese exchanges are still no fee, admittedly at odds with gog1, then it explains how they pay their bills.
I don't like it, but it is consistent with price moving down on no real developments.