In our rehab centers we have water, gatorade, and propel for drinks and various snacks including graham crackers, nature's valley granola bars, and stuff of that sort. We're a very rural department and 90% of ours calls are medical in nature. Only a few times have we had fires of the size where we've ordered pizza's and McDonalds. Most of the time our firefighters only come out for an air tank change and a quick drink, then hit the hose line again.
We are a small town/rural department most of our calls are wildland fires or vehicle incidents. For an extended incident we have traditionally relied on farmer's wives and the Firefighter's Auxiliary to bring meals after the call (which can be hours on a ripping wildland fire). We are just beginning to stock supplies and develop protocol to have rehab services on site. Gatorade, water and snacks are going to be a must. I welcome any other great ideas.
Our Rehab truck is stocked with the usual water, and gatorade for hydration. As for snacks we have peanuts, natures valley, and the other typical snack munchies.