Because only the rich, the people who own/control these mega-corps, are the only ones receiving gigantic funding "bailouts" from the government, meaning they don't face the fallout of their stupid mistakes. It's basically a free ticket to steal money from the American public, but only if you can afford to set up a mega-corp and let it fail while you "earn" multi-million dollar salaries every year regardless of performance...
Are the people who own mega-corps richer then those that own regular corps? Generally speaking, stock is not owned exclusively by the super rich. The lower end of the spectrum (those that also have no savings) do not own stock. Anyway, haven't they lost most of their money already?
On top of that this isn't for the shareholders. It's to keep a financial system from collapsing. You can argue that it wouldn't have collapsed. That this makes it more likely to collapse etc. Sure.
