One thing nobody mentioned 'closed campus' vs 'open campus' - a closed campus is one where the students are prohibited from leaving the school grounds during school hours. An open campus is one where students are allowed to leave. (And there are combinations - maybe freshmen are banned from leaving and the others are allowed, or maybe only seniors are allowed off campus.)
So for students with wheels on an open campus - lunch is frequently at the nearest pizza place or burger joint.
(This info spans the 1960s to the 2000s. I went out to lunch and my DS went out to lunch (30 years apart.)
On a closed campus the students will complain about the 'prison guards'. On an open campus, the neighbors will complain about the noise during lunch time with all the students waking by.
And in an urban, suburban setting, there will be restaurants like pizza and burgers, within a few blocks of campus.
And (at least currently) it's possible to have food delivered to a high school. Enterprising students on a closed campus might take orders for pizza slices then order in a couple pizzas.
