The other thing to remember, in the U.S., is that parents are constantly in a one-up war with each other. The two sides of that spectrum are "my kid's got the best lunch for him ever" and "my kid's got the most awesome lunch the other kids will be jealous of". This is why packed lunches should be flat out banned, in my opinion, but I concede that it's a parent's ultimate choice in how they raise their child. On the flip side of that, it's also their responsibility to do more than write articles about the poor state of food and actually try to do something about it.
I'm far too lazy to find the reference, but I recall that empowering the children to do it themselves has worked more than once.
You want to ban lunches because someone might feel bad about it? I went to the wealthiest (public) schools in the wealthiest town in the wealthiest county in my state. A place where kids got on that MTV Sweet 16 show, and not once was this ever a thing. This is the same argument they used for uniforms, that people would get made fun of. Never once saw that either. It's a joke. Sorry not everyone is wealthy, but that is a solution looking for a problem.
I've got two kids in school, and have honestly never seen that kind of competition. We pack lunches for our kids. Typical fare is a sandwich and a piece of fruit. Sometimes it's leftovers, and maybe cut-up vegetables if we run out of fruit. We bake our own bread.
If parents were competing over lunches, I'd see pictures of those lunches on Facebook, because that's how parents compete nowadays -- like the pictures that people share when they summon up the courage to cook a meal at home.
I'm far too lazy to find the reference, but I recall that empowering the children to do it themselves has worked more than once.