As cheap [frugal] as I am, I would not resort to this. But it's good, and a bit surprising, that one could do:
"Food costs can get pricey at the fair, especially for families. If you don’t mind skipping out on fair food, preparing your own is a great way to save money. The fair allows guests to bring outside food and coolers, as well as nonalcoholic outside drinks."
https://www.mprnews.org/story/2024/08/15/minnesota-state-fair-101-guide-great-minnesota-get-together-2024