Sadly, the rat-box shelters are LEAVING A BIG TRACE just existing. Dismantling them is the first step in the right direction. Another thing---many national parks have easy rolling couch potato (vehicle) access which causes gas-huffers and the wheel addicted to get too close to whatever is "wild". The solution is simple---close the roads. Instead of kicking all humans out, kick out the cars. Make it difficult to reach these spots. They have to be earned.