Greedily and fraudulently selling mortgages to people who couldn't afford them was the root cause of the financial crisis:
Some people are probably guilty of criminal activity. At a minimum I question the morality of people who sell products at a premium they know are valueless.
Ah - You conveniently set aside the ones that signed off on a mortgage that had escalating clauses for interest - Right they are innocent - Lots of people had a hand in it and I am not absolving anyone - But Fannie Mae and Fanny Mac were told what to do by the politicians - make home ownership available to Americans