The curb weight of the 4WD Escalade is 6040 lb (Cadillac | Escalade ESV Dimensions) and of course there are still Hummers on the road. But even if the weights of some are under 6000 lbs, or only over due to occupancy, they are still near the limit for roads rated for 6000 lbs., so even on roads that don't carry heavy trucks there is probably some road damage caused by personal vehicular transport. And even in the cars themselves don't cause much direct impact damage, the more car traffic there is, the more lanes you need to build and maintain.