I don't know but I am guessing there are a few different players in what I call the specific check in space, but I only know one: FoodSpotting. And if there are others, FoodSpotting sure has the best seat in the house. Checking into a book, or movie or music is not actually checking in. It is not location specific. The Like button by any other name.
Much of the special going out involves eating and drinking for many people. And each such check in place, by definition, is a business. Caching. As opposed to when someone checks into Central Park - and people do - that is hard to monetize. Street vendors: don't count on them.
