I don't know how popular they are now, but about 13 years ago I was vacationing in Anchorage, AK and there were many "coffee shacks." Simple sheds with at most two people working, that sold fairly good coffee/espresso and a few pastries through a window. Unless one was near a park there was no where to sit, so you got your coffee and left.

A few years later I noticed that there were some franchises springing up with the same model, but the entry prices were insane. Might as well start a McDonald's!

Anyway, my point is that perhaps the expectations in the US are regional and in some locations, the model you're describing might work.