The reason you see all of these people selling is not because they're doing it on purpose, their mining and using Cryptsy's auto sell feature. Most likely this is a multipool who has mined a few blocks and offloads them at a little bit above market price.

So, the only way to avert them from driving down the price, you'd have to have buy orders near the lowest sell order, and enough to cover it as well.

This price is meaningless at the moment, no sensible investor would be selling at these prices (except lunatics), we just have a large miner problem.

I could buy up all of the orders all the way up to I guess 4000, but that means absolutely nothing. I wouldn't have any more BTC at all to support that price. I know this because I have done this on several occasions, with several BTC at a time, only at a lot higher prices.

Also, only insane people would sell at the 100-200 satoshi range, so it will never reach that 8 million buy. No one would even sell that much anyways. (No suicide today silencesilence).