One time we were in a National Park, and DH pushed our car caddy back behind the picnic table. The host stopped by and politely asked us to move it on to the paved part of the pad. They explained that it can kill the vegetation. The wild horses do roam freely there, and depend on the vegetation to survive. After they mentioned it, I could see their point. We apologized and moved it. Wasn't done deliberately on our part, and we corrected the situation immediately.
We always try to make sure we follow the rules, but if we mess up and it's pointed out to us, we correct it and make a mental note to not do that again. I appreciate having the privilege of camping in our National and State parks and don't want to jeopardize that.