I am not a gambler either, nor a fan of shows, but I really enjoy Vegas. Wandering around watching the people is a lot of fun, plus seeing the sights. I really, really want to go back soon.
Go to Hoover Dam if ya get the chance.
Go to the upscale casinos, like the Venetian (I stayed there last summer), the MGM, Cesar's Palace, etc. Just wander around. Don't bother gambling, just go see the other attractions.
Believe me, I HATE the thought of gambling. I'd much rather explore the town.
Vegas is a bit overwhelming for the first time. The night we got there, I just wandered around the Venetian for 4 hours or so, getting my bearings and watching people and seeing the sights. The people I was traveling with were pretty much only interested in gambeling, so I ditched them and headed out on my own. The Strip is beautiful at night, all lit up. You also need to go see the water show at the Bellagio, and the pirate show at Treasure Island.
Legal prostitution?
I don't think prostitution is legal in Vegas.