It's legal in some parts. I googled it.

http://www.sexuality.org/l/workers/nevada.html

It says in the faq that it's still illegal in las vegas and reno, as well as other popular gambling sites. Something about mixing gambling and prostitution being too much sin at one time, thus fulfilling scriptures and causing the sea to turn red with blood, the genitals bleeding of their own accord, and the gnashing of teeth, I guess.

They have it a lot in those HBO specials. Yeah, I watch those. I don't know why, some are just funny. Especially that one girl who's in spiderbabe and lord of the g-string and etc.