It’s not supply and demand

Oregon funds its roads by gas tax. People there have carpooled and found alternatives to driving to the point that the state is trying to find new ways to generate revenue.

Demand has fallen on a statewide level. You would think that would have some effect on gas prices–I mean, prices vary within just a few miles of an airport, so if a whole state changes its demand it should show, right? Lower demand = more supply = lower prices.