This is another government intrusion into our lives. I wouldn't characterize it as liberal, per se. This is actually a Head Start program. I would guess the policy was in effect during the Bush era as well.
OK, even so, it's more a thing of governmental control than liberalism. I suppose they don't want parents giving kids in the Head Start program lunch because:
1.) Head Start meals are subsidized. If too many parents fed their own kids they would lose or have that funding decreased for meals. "Use it or lose it."
2.) Low income parents might feed their kids junk food.
My three children still at home hate our school lunches. Some days there are not enough food and they do not get lunches and the food they get is lousy and expensive. We send lunches to school.
I hear that a lot. I'm glad that our school district has somewhat decent lunches, as making lunches is a hassle. And there never is enough for a 16 year old boy!