I'm surprised that you don't know that most Western men have used prostitutes in one way or another. Just look at the Buck's night tradition where it's customary for the groom to indulge in wild sex.All you have to do is read through the updated Topix forum threads. It's pretty clear who's looking for call girls, boys, etc.
Then we have viagra which is mainly used outside marriage.
Don't forget the custom of wetting a boy's whistle i.e. having his first sexual experience at the fathers instigation with a prostitute.
I could go on.
You seem oblivious of the sexual mores in your own society.
It's also common for both older men and women to choose younger partners. Look at Madonna who has oral sex on stage with her new toyboy.