Yeah let's take away the task of parenting...
Parents don't have much to do with what a child decides to buy at a school lunch.
In any case, these rules are fine, though I'm not surprised people are complaining. If you don't like what's being sold, many students can just bring their own lunch. I understand not all students can afford to do that, but school lunch was never exactly great to begin with. If your going to sell kids crap, might as well be healthy crap.
They have almost everything to do with the choices their kids make...
Kids are smart, but they are barbarians. You really think they're going to listen to what their parents tell them to eat when they aren't there to enforce it?
Have you ever been a kid?