Yep, and if you're from the correct part of southeast Iowa, it comes down to a battle between MaidRites and Canteens.  The Canteen is a tiny, tiny little diner in an alley in Ottumwa.  There are about 14 stools at a lunch counter there, and all they serve is the sandwiches, soft drinks, and homemade pie.  Natives that have moved away and come back to visit will stop in for a Canteen before they go see their Grandma.