Not just that, many of the subprime mortgages were missold to people who could actually obtained a much cheaper prime mortgage that would've been less profitable for the bank.

(Often on the basis of race - which is one of the things that makes all the people who blame the Community Reinvestment Act for the mortgage crisis really misguided. All the CRA did was ban redlining, a practice where banks excluded everyone in predominantly-black areas from prime mortgages even if they'd otherwise be eligible, leaving expensive subprime mortgages as their only option.)