I kind of got a kick out of the initial response to the thread starter. The average girlfriend/spouse will cost you alot more than any prostitute anyway. More power to you. I say...call her a whore, fuck her in the ass and hand her a gift certificate.
I forget the name of the movie...but I remember a great line where some animal rights activists were demonstrating in front of a building when a limo pulls up and this woman steps out wearing a full length mink coat. One of the demonstrators yells "DO YOU KNOW HOW MANY ANIMALS HAD TO DIE TO MAKE THAT COAT?" and she yells back "DO YOU KNOW HOW MANY ANIMALS I HAD TO FUCK TO GET THIS COAT!"
I trained my dog to do what I want him to by holding a milk bone in front of his nose. If the concept works...why not!