States already account for this. For example, in Massachusetts, if you purchase a vehicle in a different state, you are subject to a "use-tax" which is equal t

States already account for this. For example, in Massachusetts, if you purchase a vehicle in a different state, you are subject to a "use-tax" which is equal to the Commonwealth's sales-tax. Otherwise, car dealerships would be non-viable in MA – everyone would take a quick jaunt over to NH to buy their cars.