Vegas buffets, and pretty much everything else, used to be cheap when the Mafia owned & ran the casinos and took their cut from the gambling. The Mafia were forced out, but are still there and now control pretty much everything else — construction, transportation, food suppliers, sanitation, etc.
free buffet, 50 cent one-deck blackjack, all gone....
With the Vegas Strip now a duopoly the need to use cheap food/buffets as a loss leader to get people inside the casino has disappeared.
You forgot Harry Reid.