What I don't get is how making pornography is legal and tantamount to prostitution (paying someone for sex), but prostitution itself is not.
The pornography industry is highly regulated by the government, iirc, and the cameraman isn't allowed to participate in the sexual acts depicted. Therefore, it's not as simple as bringing a camera when you go to pick up a hooker.
It's (I suppose) similar to why marijuana is illegal and alcohol/cigarettes are legal. All of them are bad FOR you in some way, and the latter two are legal. Why? I'm not sure.
But hey, it's an interesting concept.