HFTs provide liquidity, which by definition is providing what people want to buy/sell, when they want to trade it and it the desired quantity.
> HFT is like hiring The Flash to be your grocery store clerk, who notices you reaching for the milk, and runs in to empty out the shelf and raise the price by 0.003 cents by the time your hand gets there.
This is not what HFTs do. They can't see your "hand reaching", they see your quote hit the book at the same time as everyone else. It's not magic.
They're literally the market makers. Your complaint appears to be that they're good at reacting to new information, i.e. being good market makers.
Every exchange gives "good standing market participants" aka HFT market makers first dibs on orders. If a gallon of milk goes on sale and I'm waiting in line with a market maker I will never make the sale, it'll go the the HFT firm every time.
Or are you talking about exchange hosting, where you get lower latency if you pay more to colocate?
You do understand how that's different from HFT, right? That's more of a market making job. HFT is like hiring The Flash to be your grocery store clerk, who notices you reaching for the milk, and runs in to empty out the shelf and raise the price by 0.003 cents by the time your hand gets there.