Can I make a quick suggestion re: open food? I think if you're going to add cereal, tortillas, rice, pasta, or any other sorts of dry goods, only add it to the bin if you can put it into a ziploc bag. that way, the contents are sealed, both for freshness sake and also so food doesn't spill all over, I would also suggest labeling said ziploc with the date, so whoever has the bin afterward you can throw it out if it is past due without having to taste test any possibly stake food.
I know we all probably have spare ziplock bags on our list of things we bring to disney, but if my bin doesn't have any in it, I will be happy to add some when I'm there.