The New York Times has a report on banks colluding with online loan sharks to defraud their low-end customers:
1. The banks charge overdraught fees when the loan sharks’ automatic withdrawals cause the borrower to be overdrawn.
2. They will let the loan sharks take only the interest on the loan even when the borrower wants to pay it back in full, so that the loan is rolled over and another round of fees can be levied.
3. When people try to stop the automatic withdrawals, the banks do not honor their requests.
4. When the borrower tries to close the bank account against which automatic withdrawals are being made, the bank will keep it open and charge fees every time the loan sharks come for a withdrawal.

Yet another incentive to stop patronizing regular banks and find a local credit union instead.