One of the reasons it’s called “sex work” is to cover things that aren’t explicitly money for penetrative sex. It also covers things like pornographers, strippers, domination, kink-play, and intimate massage.
It’s not always someone being bribed into doing something that they don’t want to do, it’s sometimes someone being paid because of their skill or appearance.

If prostitution was legal then people could ID beforehand, which should lead to less abuse.