Simply put, basic banking functions contribute to the economy. The economy can do more with the availability of capital basic banking provides.
The problem with that is that banks no longer need to rely on private investment to provide capital via loans. They can just get it from the gubment for virtually 0% interest and virtually risk free.
What incentive do banks have to treat their small-time, private investors (people like you and me who have a savings account) well? I mean, if the bank can borrow the government's money at 0% interest, why would they borrow mine at any more than that?
You want to make banks treat consumers better? Stop the government gravy train. Raise interest rates. Force banks to compete for investments, rather than giving them as much risk-free free money as they want.