>Its not the winning that draws people to watch poker <
Also most people know how to play poker and like to watch the hands and think what they would do. Yes, you can do this in chess...IF you are a chess player, which most people are not nor have any interest in becoming, no matter how cute the girl who is explaining the pros and cons of queenside castling.
The other reason for Vegas is that the organizers continue to believe (as do several people in this forum), that all you need is lights, camera, action in tournament chess and suddently ESPN will be proferring a broadcast contract.
Some people can get too close to chess, too passionate about it, and forget that for the rest of the world, it's just another nerdy boardgame.

No matter how many showgirls you hire, how breezy and gee-gosh your commentators are, or how absurdly fast your speed chess time controls are, that's not going to change...you can build it, but they won't come.