There's nothing inherently profitable about abuse. Making your workers miserable generally makes them less productive. The thing with banks is that they aren't

There's nothing inherently profitable about abuse. Making your workers miserable generally makes them less productive. The thing with banks is that they aren't productive in the first place. They're scalping off whatever they can get, with fierce competition. If you're fresh out of college and get hired into these places, you can't just walk away without risking your whole career. It's a monopsony. That's what enables abuse, human nature takes care of the rest.