Is it wrong for a guy to use an adult hook up site?

A friend and fellow church member showed me today that he has an ad on a hook up-sex site. His photos on it aren't explicit (he just has a pic of him on the beach without his shirt) and he just has a basic run down of what he's looking for in a 'hook-up.' Having said that I can't help, but, think that there is something odd about this. His explanation is that he's not into getting married now and is not into the bar scene, but, he still wants, erm, some once in a while and he can't figure out another way. Am I being a prude or is he doing something wrong?