> Midwestern emigrants (who didn't think they were good enough for NY, and didn't think they were good looking enough for California, so ended up in the second city.)

Or because it's close to home and way more affordable? Also, while winter sucks, I'll take a Chicago summer over both those places every single year.

I grew up here as well. No one thinks deep dish immediately when talking about getting pizza. It feels more like a once or twice a year delicacy than anyone's go-to pizza.