Amusingly, my first encounter with a pretzel bun was in my college cafeteria – Burge Hall at the University of Iowa, ’98-’02. Today they’ve been remodeled into a food-court type of setup, but when I was there, they were still doing the old-style institutional food. Better than grade school or high school, but nothing to write home about except for a few dishes.
They opened a dedicated sandwich line and called it the “Clinton Street Deli”, after the street Burge is on. The meats, cheeses, and veggies were about the quality you’d expect, but one day there were pretzel buns being offered, and they were like a revelation. They alone tripled the quality of the sandwich.