We, men, sometimes are not thinking about their reason.
Do you think girl would be happy to have sex with strangers?
How about if a man, working as male entertainer, then get booked by 50yrs old lady?
How's that? Think you can get excited with that?
And if we consider that they are a girl. Their feelings are more delicate than us.
Even if you don't really know their reason for working, and just guessing wildly after considering those things above, don't you think It would be stronger than a mere ice to make them able to work almost everyday?