Unless I'm really pressed for time, I try to find local places to eat at whenever I'm on a road trip. Here in Missouri (and doubtless in other states throughout the Midwest), a lot of towns on or near the major highways will at least have a diner-type place or a drive-in, and often a barbecue, Mexican, and/or Italian restaurant as well. Usually these restaurants will be found either along the highway or a little ways off it, in the downtown area (often on the courthouse square, if the town is a county seat). From my experience, these small-town restaurants tend to get me in and out in a reasonable amount of time (usually within 30-45 minutes); whenever I'm on a long road trip, I make sure to build that into my time calculations, as far as figuring out when I should leave. (If the meal takes less time than what I built in, then I arrive at my destination earlier that expected - bonus!)