I've always wondered the same thing...Perhaps thats why I'm hesitant to seek out a cache site of my own. I fear stepping on someones "toes" or getting a denial when asking for permission... Some of the public accesses aren't the greatest places to hide a cache either.. From experience, I'm very disappointed to find such nice places getting trashed far back into the woods, which makes it an unpleasant trek when hunting for a cache. You never know what nasty stuff you're apt to step in....
JMHO
Silva, of the forest
Beneath you, feel the Earth.
Above you, feel the Sky.
Around you, feel the presence and the Power
of the Trees!