Some other ways Brokers make money: Market Making operations that leverage the same infrastructure and market position, Interest on Margin, Stock Loan/Borrow ac

Some other ways Brokers make money: Market Making operations that leverage the same infrastructure and market position, Interest on Margin, Stock Loan/Borrow activity with other Brokers, and Market Data Access. Still with these items, I agree that a move to 0 commission trading will cause a shift.