Because the majority of that $50 billion is going to the US Treasury.
And the proposed taxes on banks is in response to them receiving federal welfare, then turning around and wasting taxpayer dollars on lavish bonuses.
I'm all for the banks going to private investors to get them out of trouble, the problem is, they looked to Uncle Sam for a bailout. When that happened, they lost all their rights.
And if they try to raise fees on consumers in response, that is fine with me. I'll take my business to a bank that didn't get a bailout and isn't raising it's fees.