I knew the Sierra Club was full of it in 1980 when I heard a report on the radio by the Sierra Club while at work that fragile Alpine tundra plants in Rocky Mtn. Nat. Park were in danger from tourists walking on them. I had just been up on Trail Ridge Road the day before and had seen those "fragile" Alpine tundra plants pushing up through the asphalt walking paths the Park Service has up there.
Never mind that the amount of Alpine tundra accessible by car is indescribably miniscule in comparison to the tens of thousands of square miles that aren't.