we do this same thing every year .. we go to the town festival .. and the kids all play with thier glowy necklaces , we them each one "super toy" we usually eat dinner there .. and its the infamous italian sausage sub and french frys .. then comes night time when the fireworks start and we want orange slushies or lemonade and fried dough!!!! ( fried dough UGH ) but its soooooooo good to eat while watching the display ... this year we are going to a bbq first .. and I'm going to bring some fish and veggies to grill for myself and hopefully try to fill up as much as possible before going .. neither of my kids will eat fish or chicken so I'm jsut going to let them have a hot dog with lots of fruits and veggies ...
as for the night time ... I think I am going to stick to the lemonade and fried dough

its just to much of a tradition... Im not perfect

its my treat ( for the YEAR) and at least I'm cutting out the sub and fries
maybe if your packing food to bring with you .. you get make them a sandwich .. like a pb and jelly or turkey or ham or something and the suggestions for the festive mix of fruits is a good idea too! easy and good ... and maybe some cucumber slices or soemthing .. not sure really how picky your kids are ... mine are REALLY picky