Earning potential depends more on the degree subject than how advanced it is.

The most educated whore I've ever encountered had an MA in history, along with BAs in philosophy and European culture/literature. Being able to discuss the Islamic conquest of Persia and quote Descartes helped her sell herself as a classy courtesan, rather than a Craig's List hooker, but it couldn't get her a highly paid job in the real world.

Not that she earned anything like $10,000 a night, I doubt she earned that in an average month. But then she wasn't exactly Playboy model material...

There are people in my company's call centre with that level of useless education. I was just chatting with the receptionist about her BS in zoology. Wouldn't be too shocking if one of two of them did a bit of whoring on the side.