Two years ago for Christmas, my MIL got us season passes to Cedar Point. Our first trip of the year, we got lunch for everyone at the park. It cost us around $100. Right then and there, DH and I said that we couldn't afford to do that everytime we went to the park or that would have been our only trip there for the summer at that cost. We sat the kids down before our next visit and explained that if they wanted to go to the park that we would need to park our lunch and/or dinner to take with us. The kids were A-OK with it!
So from that trip on, we packed a picnic. I invested in a nice picnic tablecloth and clips, we got a new cooler and Bubba Keg thermos.
We packed lunch meats and cheeses, different rolls, buns and breads to keep it interesting. We'd do chips, pretzels, pasta salad, fruits, veggies, fruit snacks, Cheez-Its, string cheese, frozen yogurt tubes, etc for our sides. I'd do lemonaide or Kool-Aid in the thermos. Cedar Point has picnic areas on both sides of the enterences and we always found that if we drove up to drop our things on a table, there were always parking spots open right there!
During the rest of our trips, we allowed everyone one snack per trip but the snack couldn't be more then $5 per person and if they wanted pop, that was their snack. Most of the time, I would share a snack with DD so our total OOP for the day was gas + $20-$25 for snacks. MIL bought us season passes again this year and we plan on doing the same thing. DH got a little charcoal grill on clearance that we are going to try out to see if we can do hot dogs or brats on this year.