There is no universal answer to your question.
Every dude is a story for himself.
Yup. A few dudes are in it because it pays quick bucks, so that they can finance their lives (and possibly addictions) with relative ease.
The others are in it because escorting can be easy. As Undercoverman pointed out, it does not take a degree in rocket science to start making cash on the fast if you choose to escort. I once met a guy who went into escorting to buy himself a very pricey car.
I am sure that some guys get their thrills out of the fact that they are getting paid, i.e. undeniably recognized as being really worth something to someone. If you have low self-esteem issues, the fact that money speaks much louder than just words, may or may not work for you.
I have two friends who are escorts. Both of them actually have very nice, regular jobs, and are pretty hottt dudes, too. Both of them say that the extra income comes in very handy with the expensive designer items, fancy holidays, and some emergency savings, too. They have been quietly escorting since their HS days, love NSA, m2m sex, feel that there is something attractive in every dude who is willing to spit out some serious cash for their services, etc..
I have yet to meet an escort dude who is unaware of the fact that some dudes out there judge him, or do not approve of the choices he has made. Guys, save your breath. The escort dudes, porn actors, strip boys, etc., will keep on running their show regardless of what we or anyone else here has to say.
If they wanted to flip burgers at $9.00 per hour they would be doing that already.