In a post-9/11 world, I took an airplane to university and back, and on a regular basis from [SMALL CITY] airport. I could, as a disorganized young adult, be at the airport within 10-15 before boarding time with luggage to check.
Pre-9/11, my family travelled internationally and it was always a 3+ hour, pack-a-lunch affair to be at [MAJOR CITY] airport.