Nonsense. When stocks become overbought, or when a company screws up, people short the stocks in question. That's not "manipulation". It's "good sense". The idea is to "make money".
Why not play both sides of the market, as circumstances dictate?
If you didn't have market makers to short the stock then you could have an unbalanced market. Imagine you wanted to buy shares of ETGMF however there were no sellers anywhere. So you'd have one of two options, to either forget about owning the stock or else keep raising your offer until someone with shares decided to sell. You'd have the wildest swings in stock prices imaginable! The shorters assume risk and that's what they are expected to do.
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