I don't know a thing about how Vegas sets its books, but my sense is this: Utah is a low volume bet. Vegas wants maximum volume on all their bets, not just the ones everyone wants to bet. They'll always get volume on the big market teams whether they suck or not because those teams have lots of fans willing to kick in a twenty for the hell of it. But Utah? Small state, a culture that frowns on gambling, and a team that isn't highly visible nationally. So if they set the odds too realistically, nobody bets it. Give extra "points," and they get more bets. The odds of Utah winning are still astronomically low, so it winds up being a very well leveraged play for Vegas if they bump the odds to the breaking point and beyond.