Hey Poodle enlighten us how they are wrong !
Rape is non-consensual. Assuming it is consensual, it can't be rape (even if the punter doesn't pay). There are various exceptions, but generally, that is the rule. So, if anyone (let alone a WG) consents to sex conditionally (i.e. on payment, or if you will wash my car, or if you will marry me)... and you don't go through with the condition... it is not by itself rape - as the consent is there (I won't go into the state of mind of the person promising to do something for sex and knowing they won't go through it - that is more theft).
BTW - AFAIK, one can't steal sex.. although I could be totally wrong - never looked at it..
Theft is effectively permanently denying someone of what is rightfully theirs dishonestly. There is a famous case of dishonest which is now known as the Ghosh test, and basically is "a jury must first of all decide whether according to the ordinary standards of reasonable and honest people what was done was dishonest... If it was dishonest... then the jury must consider whether the defendant himself must have realised that what he was doing was by those standards dishonest."
So, the people receiving "free" sex are not denying the WG sex..in fact, if that were the case, it would be great because we would never stop having sex with them so as not to deny them sex. They could be accused of denying them the cash that was promised for sex. It is (in a legal contract - of which all but those in a "brothel" - which are illegal) what is rightfully theirs. However, from what everyone wrote, it was their intention to pay and an action of the WG that caused it not to happen. In fact, some went back and tried to pay (others decided not to - there is no law that requires you right someone else wrong).
Seriously - I go see a WG; I intend to pay.. I may have forgotten, she may have dashed off, or made it free, or wanted to see her mates more than collect my cash.. I have done nothing dishonest and it was consensual (i.e. she didn't at any time say or give a reasonable man belief that she hadn't consented - which is important as otherwise they would have explicitly say no). Am I really committing rape or theft?
Of course, if the WG said no or made clear that I was not to have intercourse with her and I continued/forced, or I did a runner.. definitely in the wrong and would hope the full force of the law would land on me...