I think the reason I'm so obsessed with not liitering the outdoors was that when I was younger, I saw a TV commercial with "Iron Eyes" Cody dressed as a Souix Indian. He rides his horse through beautiful valleys, by rivers and waterfalls, and eventually stops near a highway where a passing car throws trash out the window that lands at his feet. As he looks up, there is a single tear running down his cheek. There was no dialog at all. It didn't need it. It was one of the most emotional things I have ever seen on TV before or since.

Any time I see litter, that scene pops back into my head.

Semper Fi!