Related, but still kinda off topic, I recently learned that the Sno*Drift Rally in Michigan is one of the toughest rallys anywhere because Michigan doesn't allow metal studded tires on public roads, therefore the rally cars can't be fitted with them either.
Kind of strange, for if you've ever seen the fully loaded logging trucks which traverse those roads year 'round, the damage caused to those roads by 70 maximum rally cars on studded tires would be minimal by comparison.