You know, there's a much shorter answer to all these questions: Because they can. What the fuck are you gonna do about it, bunky -- turn off Dancing with People Who Used to be Sorta Well-Known and register your disapproval somehow? Not bloody likely.
I don't know if it's a more standardized reference in financial circles, but I like the "shadow financial system" descriptive Roubini employs:
Although "casino running on borrowed money" is also pretty accurate.
Finally, First Draft has an excellent takedown of the billionaire welfare queens.
And the minute the majority of rubes out there finally disabuse themselves of this notion that each of them will somehow get a cut of all this phantom finance and percentage-point diddling, maybe then we can cut these grifters loose once and for all. Not that waiting until we were $2 trillion deep into two endless wars wasn't bad enough. Maybe it does take going under to encourage fools to finally learn to swim, and let the weasels drown.