Banks are already making waaay too much money thanks to giving people less savings interest while giving people higher rate loans and keeping all of those money in the bank instead of actually giving people banknotes which means they are capable of using those "numbers" to invest into companies as well.
Take a look at my countries stock market, all of the public companies are either owned by banks or at least they buy as much as possible even if its just 30% open to public they own like 27% of it and give the rest to regular people to have fun.
It means they literally own all the open to public stock market companies in all of my company anyway. It doesn't make sense to charge couple dollars a month from each person as well. I mean they are making literally billions a year, why try to screw over the little guy. Government finally said that is enough and they cancelled it.
Banks are so ruthless and shady that they are still charging people for it but if you give them a paper saying you will sue them and get more back later on, basically a warning, they give it back to you. If you don't, they charge it and you let it be, than they still earn money.