I think that explains it. The singular Carl's Jr in a nearby city was always busy, for a similar reason. it closed during covid, for whatever reason, and the next nearest one is at least 2 hours away. Compared to the 6 McDonald's in my metro: 4 Taco Bell, 3 Whataburgers, 5 Wendy's, and 4 Open BKs out of 7 that were open prior to 2020.
The Raising Cane's is always packed to bursting, too, because there's only 1 in the area.