This idea is not my own (I’m not sure I should name the person involved), and it involves something google discourages as “click fraud,” but next time you feel like a bank has charged you unreasonable fees call them and tell them that unless they rescind them you’ll go to google, find one of their ads, and click it enough times to double the price of the fee. It’s a modernised version of the old scheme of sending payments in coins with insufficient postage (where the bank apparently receives a fee to claim their mail).