Well to be fair Next and Alinea have been dramatically successful with the model. And for that class of restaurant, I much prefer the model of "buy ticket" to "call and be told there is nothing available".
But how many of those restaurants are there really?
There could be more of them with this kind of system.
Probably at least 5 in every major metro, and more in NYC, Chicago, and San Francisco. With the current customer perception, that is: for "destination" restaurants, like Alinea, Saison, Ko.