I used to think that too, but this excellent piece from Matt Levine explains why that is not really the case: https://www.bloomberg.com/opinion/articles/2021-02

I used to think that too, but this excellent piece from Matt Levine explains why that is not really the case: https://www.bloomberg.com/opinion/articles/2021-02-05/robinhood-gamestop-saga-pressures-payment-for-order-flow https://www.bloomberg.com/opinion/articles/2021-02-05/robinh... Retail traders benefit from this, and on Schwab, for example, they show you the dollars of price improvement the got you.