The only one I've seen so far is a townie who lives in my apartment complex who is a thief by profession. I was a bit confused seeing her in the crook gear.
There is a glitch that makes people stay in their work uniform when doing their walkings-by. Perhaps this is what you'd encountered.
I give them "underworld passes" (one of Inge's color keys) along with the vampires, witches, werewolves, etc. Most of the neighborhood stores have a secured back room with poker, shady dealings, and the planning of riots and revolts.
Dude, that sounds awesome. It's a brilliant idea. I'm glad I thought of it.