Much less, and it was more expensive. The total cost of market making has gone down substantially with HFT, mostly because a small firm replaces a large army of floor traders.

There were still market makers that provided liquidity. Algorithms can just do it faster than people.

I want so many people in these threads to travel back in time so that they can tut-tut the market makers for wearing lifts in their shoes.

I don't get it. Reminds me of a blog post were the guy discussed a Portuguese stock, construction industry if my memory does not fail me, that has a "very low" trading volume.

When I looked up the stock, (I think the stock was very expensive), trading volume was like 1 Share every 6 months or so. Yes, I guess you could call this "very low" trading volume. So where would HTF come in here?

An HFT would list buy and sell orders on the book so that if you wanted to buy or sell, you always could.

And cheaper