No-one is being made worse-off by HFT except professional market-makers (who are being outcompeted) and perhaps professional buy-side traders (whose secrets leak out faster), both of whose job it is to understand the market. If you're a nonprofessional you should be investing with Vanguard or the like, and you benefit from HFT. If a layman with no expertise tries day-trading they're going to lose their money either way; we do have "must have this much money to be allowed to trade" laws, but those are controversial too for obvious reasons.