Its obvious you have never ridden in Kansas. Believe it or not, Kansas is not flat. The eastern third of the state is mostly rolling hills. The western half is undulating. 1/4 to 1/2 mile long rises and then about the same declines. Over and over and over and over.
I only remember one hill in Kansas that gave me problems, I think it was near Toronto Lake in the Black Hills between Chanute and Eureka on the TransAm. Of course I was low on salt and water by the time I hit that ridge.
It would be generous to call the rises in the western half "hills."
IMHO, the point remains sound, that a cyclist from Kansas should probably buy lower gears to leave the state than he would need to stay in the state. It's amazing how the definition of "normal" changes with location.