It attracts all kinds of people. It’s certainly safe to say that there are some “bad guys” in the field of casual sex. All things considered, they usually don’t hide the fact that they can be… well, bad (you know, by social standards). Therefore, you should register with a paid professional. Free? NY strippers.
You want to avoid free online sex sites because they attract a lot of curious and malicious people. No one in their right mind would pay to sign up for a free sex service “just to see what happens”.
Also, criminals prefer to have fun on free websites (including free sex sites) because they know they can hide much more accessible. With a paid service, you can always be traced with the plastic card you used to pay your rights – unless the credit card is stolen.