So the executives in the financial industry, various investors, hedge funds etc. profited by lending money to home buyers and selling these mortgages to others?
Kind of. They took these mortgages and securitized them. Securitization is a fancy word for the creation of fictitious products called "securities" (which are themselves based on actual assets that are expected to generate income). This is how the game was played: the get-rich-quick Wall Street crowd peddled these subprime loans that they knew very well were predatory, created a bunch of abstract securities by using the mortgage as collateral, packaged them with fancy labels called MBSs-CDOs-CMOs, persuaded credit rating agencies to attach AAA labels to some of the securities, sold these to investors, exploited accounting loopholes to create shell companies called Special Purpose Vehicles (SPVs) in the Cayman Islands and other tax havens, and transferred the junk securities to the balance sheet of the SPVs. So by the time they were done, they had taken crappy mortgages and converted them partly into AAA securities, partly into lower rated ones, and partly into trash that was no longer on their own books (these are the various "tranches" we keep hearing about). And then they did it again and again. They also gave themselves fat salaries and huge bonuses (try the $490 million Dick Fuld made during his tenure as the CEO of Lehman), and engineered their own payoff in a way that allowed them to have it taxed at the 15% capital gains rate as opposed to the 35% federal income tax rate.