I guess it all depends on when you go...but that's really no different to WDW. i.e. you go at Disney peak times, you're going to pay peak prices and see little to no discounts. I've helped my friend book 3 trips to Vegas this year and I got him rates under $140/nt at Bellagio, under $120/nt at Caesar's, and under $90/nt at Mandalay Bay. I had a coworker get awesome rates at Aria earlier this year just by timing it for a down week. Also, we watch the dates to see if any other discounts or incentives are offered and get them to tack it on to his trip. I can usually do Vegas for 1/3 of the price of Disney with proper timing and persistence over offers.
As for drink prices and covers...it's on par w/NYC, Miami, LA, etc. Not saying it's cheap especially if you don't get vouchers or supplement with free drinks on the casino floor, but it's certainly nothing out of the ordinary for a premier party destination.