How often, though, are these not really "cost saving" measures so much as "nobody gets a free ride" measures?

Some schools spend a lot of staff effort managing bad behavior, to everyone's harm, that could be greatly reduced by just making sure every kid had breakfast and lunch. Feeding the kids is "communism", so it's bad, but needing to spend more on non-teaching staff to manage behavior, and getting less instruction out of teaching staff because they spend half their time dealing with behavior issues is worse.