You are paying either way and either way there will be a time when she will do it with you when she really doesnt want to (and vise versa).
As for paying when others dont have to, that is pretty much EVERYTHING in life. You have to work hard to save up and buy your first car, some kids get one free from their parents. You have to pay for school, some people their parents pay or they get government loans. Some people pay for food, others work at MCDonalds and steal the fries. There is always a point where you are working hard while someone else gets something free. I have friends that have gotten things handed to them when I have had to work extra for it all my life.
I say you do it once in your life BUT be very careful. Wear protection.
Sugar babies..... dont bother, every girl can be/is a sugar baby.
Best quote I ever heard was Charlie Sheen
"You arent paying for the sex, youre paying for them to leave afterwards."