It's a man getting laid, certainly, but who's to say that this man hasn't been laid before? It's not a perfect 50/50 ratio where everyone fucks someone of the opposite sex. And I don't submit to the monopoly theory. I imagine that it's but one reason that male prostitution isn't necessarily as widespread as female prostitution, though I also imagine that there are myriad reasons for that...
This is, for the record, not something to be used as an excuse for not getting laid. I imagine that with some effort and courage, most guys here could get laid pretty regularly. Moreso for those in college. However, women have to make less effort, and those guys who are more confident - or in the right situations - are more likely to get laid.