> geeks who believe they have outmathed a financial firm should ask themselves "Are financial firms likely to be bad at math?" and "Are financial firms incapable of hiring their own geeks?"

Moviepass was also bought by a financial firm... Come to think of it, they have many similarities. Both companies are basically handing out free money and it's unclear how they would make any profit. People speculate that both companies would make money by "selling data." Unless if Robinhood is doing something very illegal, there is no way that they could make enough money that way.

That said, I do think that Robinhood knows what they're doing. They're getting a lot of publicity right now. In the worst case scenario, Robinhood can cut costs by slashing interest rates and putting a cap on the number of free trades you can do. Their worth would plummet, but later investors would be the ones who pay that price. Overall, Robinhood would still be better off.