Depends where you go. As the visiting stat guy, I've been to some places where there was no complimentary spread, and I've been to some places that would offer me their press box food at halftime. I would gladly partake after all the home team workers and guests had their chance. We're usually talking about pizza, sub sandwich, hot dog, Frito-Lay products, cookies, and either cold drinks or hot chocolate depending on the weather. Otherwise, I'd either go down before the game or at halftime to throw a few bucks at concession stand, usually for a hot dog and candy. At my school, they'll often send up some hot dogs, popcorn, and drinks at halftime. It doesn't improve the experience for the people in the stands, but you definitely want to stay on the good side of the few print and broadcast media that remain. You don't want to unnecessarily stir up any bad PR from them.
A few years ago, our press box was overcrowded with media for a big local game. AD had assigned seating based on who all was covering the game and how many each outlet said they were bringing. The programming director for the main local news-weather-sports radio station that was broadcasting the game showed up unannounced. There weren't enough chairs to spare one for her, and she subtly buried our school and AD on the radio the next week. They announced which game they'd be covering early that next week, and she made a snide remark along the lines of, "maybe they'll have a chair for me this week."