May be related to this. I have the feeling that white rural Americans dislike "smart" people more than they dislike immigrants, blacks, city slickers and even billionaires.
If by "smart" you mean arrogant urban sophisticates who think very highly of their own intelligence then you're probably right.
Or it could mean more cosmopolitan dwellers who understand living in a connected, diverse world that's always changing better than your average rural dweller.
How would they identify that quality enough to dislike it? I'll tell you how: the smugness.
In defense of your average rural dweller, things really do move a lot more slowly in rural areas in comparison to metropolises. There's less diversity as well. So, you know, please take it easy on us dumb hicks out in the sticks. We're less connected, sure, but we're getting there.
No one I met in Appalachia or other parts of rural America was remotely mean to me when I was biking across the country after college.