I don't mind my kids getting chocolate milk at school lunch, the rest of the meal is garbage anyway so at least they are getting something semi-nutritious and the calcium they need (but not many kids get), I HATED white milk at school, the stuff in the carton tasted terrible compared to the milk at home. I have a problem when that is ALL the kids drink for milk is chocolate milk, and the family makes it such a deal for my MIL she will purchase it.
And as far as school treats go, I do not think there should be an issue if what is brought in is a nutritious cookie of muffin or cake made from scratch. What is irritating to me is when they DEMAND you bring in pre-packaged snacks. I can mix up individual trail mix packages myself for 1/2 the cost and they would be just as good as the store bought junk, but without the preservatives.
Our school has a nutrition program that has removed the chocolate milk from the lunches except on Friday's because of the high sugar content. Yet the school still serves fruit canned in heavy syrup and diet salad dressings...... and they serve the same prepackaged crap that was served 20 years ago. If you want to overhaul the school lunch program, fire the kitchen staff and replace them with individuals who have been trained to cook for institutions through a culinary program. It can and has been done successfully, and then it would not matter so much if the kids were drinking chocolate milk or bringing a cookie or what-not to school for lunch.