> because HFT's provide no value at all to the everyday person If you participate in the stock market at all, you indirectly benefit from HFTs lowering the bid

> because HFT's provide no value at all to the everyday person If you participate in the stock market at all, you indirectly benefit from HFTs lowering the bid/ask spread and therefore getting a better price. Now matter how insignificant, but the benefit is there. Of course if we're dealing in millions, not thousands, then the benefit is more pronounced, but a couple of cents here or there still make a difference. At the very worst HFT firms are a net neutral. > "make lots of money at the expense of mainstreet investors" Can you elaborate on this further? I don't see how HFTs make money at the expense of mainstreet investors. HFTs make money on the expense of inefficiencies, therefore making the markets more efficient.