It’s the age old - make a quick buck with a minumum of effort mentality.
Either work an hour serving Burgers for $10, or have a quickie with a John that THEY CHOSE for $100.
Sex sells, always has, always will. Whether they are exchanging sex for a movie and a meal, or doing it for cash - at least doing it for cash is honest and direct.
We’re talking about children. I am also amazed whenever someone on FR supports child prostitution and kiddie porn as “free market”.