Lunch counters at big box retail department stores used to be a thing. The Woolworth that I worked at in 1985 as a high school student had a sit-down restaurant that served both lunch and dinner.
And of course, there was always Kmart. This ad from 1974 presents a deal on Kmart submarine sandwiches, 2 for 79¢.
That’s about $4.65 in 2022 money. Not quite as cheap, when you look at it that way, but still a good deal.