There are 24/7 pizza places in sufficiently big cities. I think there are 2 or 3 here; I know there's at least 1. As well as a Chinese place and a Mexican place that are bomb as fuck, especially at 2 in the morning.
Fr. I could definitely get food that late living in a small rural town; but I'd have to drive to the nearest freeway exchange where the places were 24/7 for travellers. We even had a Taco Bell and it closed at 11. Like wtf?
Most decent pizza places stay open at least as late as the bars, most great pizza places stay open an hour or two later than the bars, or are open 24/7