What you're describing is the kind of cafeteria I ate at as a university student. Limited hours of operation, your choice of three entrees cooked in advance and served from steam trays, plus some stuff that was either prepackaged or could be made while they were closed and set out for self-service. And it works okay in those kind of circumstances, where you've got a large semi-captive audience who need fuel. It isn't what most people are looking for in a nice evening out, though.