Most women don't do this because of the social stigma, and those that don't care about the social stigma don't do it because they don't want to contract STDs--in particular, Genital Herpes which can be transmitted through skin-to-skin contact. I'm surprised that the article didn't examine the health risks of the business.
I'm certain that a high class escort is safer from health risks than someone who works on the street, but how much safer? That is information I'd be interested to learn.
That said, I have several friends--women and homosexual men--that have done and do this type of work. When they talk about it, they always say that they "love it." They do it for awhile and pay off some debt. Then they inevitably age out of it or go onto work that they find more meaningful. This article confirmed the stories they told me.