A lot of you have said that tourists might not want to go to a hockey game in Las Vegas but look at it this way. If you're from somewhere like Toronto or Edmonton or Detroit and were thinking about taking a vacation to Vegas in the middle of winter, why wouldn't you look at the scheudle and say, "Hey the Oilers will be playing in Vegas in January, we should go to Vegas then and we can catch a game while they're there." If you're going to be in Vegas for 3 or 4 days, spending 3 hours in an arena isn't that much time away from the casino. Not to mention the fact that you can't spend like 16 hours a day in the casino, unless you're really really really rich.
The Kings have been playing preseason games in Vegas for like 8 years now and tons of Kings fans make the trip. I'm not saying you'd get like 5,000 fans from other teams to go to every game in Vegas, but I'm sure you would get some fans willing to plan a trip to go to Vegas and see the NHL. As for the rest of it I'm sure you'd have some residents willing to buy season tickets as well as the casinos and other businesses to give employees or customers.