When I started grammar school, I was thrilled to find we got a pudding every day - at home it was just tinned peaches and Carnation milk on a Sunday, or rice pudding after Sunday lunch. I loved my school meals - my mother was a good plain cook but there was little variety in our menu.
When I started work as a secretarial trainee at the CWS in Balloon St., Manchester, the canteen offered free bread and gravy. We used to just get a big bowl of gravy and dip in the bread, so we could spend our money on a rock and roll session at the Ritz ballroom - I think it was 3d. It was some time before the canteen staff cottoned on to the fact that we were not paying for anything!
It is interesting that the main meal of the day, usually called dinner, has been taken at different times in different ages. In some Jane Austen books, it is taken at 5 p.m. but of course the coming of the industrial revolution meant that workers could only have a 'snap' for lunch and had their main meal, such as it was, after work.