this is due to the law of small numbers

rural counties have a small population
small populations are a small sample size
smaller sample sizes tend to extremes

I took this example from Kahneman. His explanation of this effect is to imagine Jack and Jill each drawing colored balls from jars. Each jar contains equal numbers of red and white balls. Jack draws four balls, Jill draws seven. Just by probability Jack will see more draws with all balls of the same color than Jill will (by a factor of 8).

which is an example of bad intuitive reasoning with statistics

People commonly make the mistake of attributing a cause to something that is just chance.

There are many ways in which this tendency to see patterns in randomness can deceive us.