Well I hadn't thought about those cafeterias in stores for quite a while, but it was the norm in the sixties/early seventies. K-Mart usually had the as did my old employer Murphy Mart in Bethel Park PA. Even Sears had one at the anchor Sears at the mall. Usually pretty cheap and mostly decent food. Sort of good the way food in bowling alleys tend to be good. Often it was in a raised area a couple of feet off the store sales floor so you could gaze out at your next purchases as you grazed on the food.