The National School Lunch program, under the USDA, is a legal requirement for all public and nonprofit private schools, feeds 30 million children, follows legally mandated nutritional guidelines, and costs about 12 billion a year. Every such school has to have a cafeteria, so, yes, it is the schools' job to feed the kids, and has been since at least 1952, when I started kindergarten.

Most employees everywhere bring their lunch. They presumably aren't children, and presumably they earn enough to buy a lunch.