It might be effect of people who have to drive for most trips, versus those who can walk or bike (alone or in combination with transit) to at least a few destin

It might be effect of people who have to drive for most trips, versus those who can walk or bike (alone or in combination with transit) to at least a few destinations. That sort of access also makes those places more desirable, and thus more expensive, and thus more likely to be populated by rich people.