Tire tax.
And bigger vehicles have more tires and wear them down faster.
And bigger vehicles have more tires and wear them down faster.
Most other people rarely leave their home state unless they live near a border.
This is the problem. More people will use them when they are in an unsafe state (low tread depth/bald/cords showing)
Exhibit A: https://en.wikipedia.org/wiki/Vehicle_inspection_in_the_Unit...