If it's "free", then why is it a "paysite", is this not an oxymoron? Most likely though, it's free of charge and you pay by taking some spyware off their hands. Ah but lets face it, if it's a pornsite with plenty of free stuff, it's probably going to bombard you quietly with spyware (at the very least, there are much worse pieces of malware out there, just wait till one of them throws a trojan on your system).