Society expects sexuality to operate under the cover of euphemisms and metanyms. This is why people talk about "making love" and "sleeping with someone" when they actually mean fucking. It's also why love movies are considered wholesome in a way that pornography is not. For sex to be acceptable, it has to be hidden under a layer of social niceties and be hinted at only indirectly. The problem with sex workers is they're too direct. They force us to confront the bodily appetites that are already there. People can't handle that.