Funny you should mention Pop Tarts. In my troop they have been banned as a camping trip menu item for many years - since before my time.
When I took over as SM the ASMs gave me the "banned food list". I asked who put it together. It was the adults. I went to the PLC and gave it to them. I said they could ratify it or tear it up. At first they tore it up and went back to poor menu choices. Within two camp outs they realized they needed better food. Rather than create a list of banned foods (adult solution) they created a series of meetings where nutritionists, dietitians and three chefs came it to talk about food choices and cooking. It became a regular thing they do once a year now.
Have had a need to "ban" anything since. It's been 9 years. Train them, trust them, let them lead. Worked great...and best of all the ASMs that supported banning learned something too.