Is it possible that check-ins are just a fad? Can you imagine doing check-ins for the next 10 years, or for the next 30 years?
But attaching useful information to real life, that's not, it's just one of the sides of a future internet of things, and I believe that is where we are headed.
In fact, why not give everything a URL and be done with it (then the like button would suffice). Maybe that is what is really happening and 4sq et al are just domain grabbing schemes.
I don't think businesses are craving for a way to give you stuff cheaper. They just want to tie you to their business. Is that really an advantage for the shopper?