Some data is skewed because this is only looking at averages. Two clear examples - western Montana and Western North Carolina, the darkest red concentrated splotches - both very mountainy and full of multi-million dollar mansions/mountain homes. Then, the people who live in these more remote areas are more likely to make less money compared to city folk. So, it skews both sides of the indexes of this chart.
The small town folk up there aren’t living in the houses “up the mountain” and likewise, the people who own those houses aren’t working at the local logging plant or the mom n pop BBQ restaurant on Main Street.
Would be better to look at percentages in this case, or even raw numbers