You could say the same thing about most HN users' software jobs, but then upon deeper inspection, you would realize: oh, there's a value here (however slight),

You could say the same thing about most HN users' software jobs, but then upon deeper inspection, you would realize: oh, there's a value here (however slight), which is why people are getting paid for it. Impacts of HFT on society: - You no longer have to pay a stockbroker $100 over the phone to take a position and hope they get you a decent price. Trading is instant and spreads are extremely tight. - Money they make is made by 1. offering you convenience (usually for an imperceptibly small fee built into the spread) or against people trying to do the exact same thing that they are (intraday trading). The intraday trading is a zero sum game, but the liquidity providing is net positive. The zero sum component only affects you if you're trying to profit from intra-day trading too, in which case, you're a hypocrite for calling them out. Amongst people who understand HFT well enough to realize it benefits them, but who hate it anyway, I think the vitriol specific to HFT is that it's a small club and they aren't part of it. Algo-trading jobs can pay significantly better than the best principal engineer jobs at FAANG (which can also be argued to be useless jobs), and those jobs are also much harder to land (think Rentech).