I'm looking for a good place to have a bachelor party dinner, fairly upscale but not exactly high roller either.
(Some of the guys aren't big on dress codes)
Also: the groom's a vegetarian (But for some reason we love him anyway.)

I don't know about the vegetarian part, but as for attire, just about any restaurant in this town will serve you, as long as you have on a shirt and a pair of pants. You might want to try a steak house like Smith & Wollensky. The one in NYC often made a vegetarian dish for my clients when I took them there. The one here in Vegas is good, has a seperate dining room, for larger parties, and is centrally located on the strip.
I hope this helps.
B.

Have you ever been to Scores???  It is a steakhouse/strip club...I know, I know, a strip club is supposed to only serve TnA, but there is a seperate section where you eat, however, you can still get a dance while dining if you'd like.  
p.s.  IM me for comp limo info