Yeah, makes me crazy too. My yard fronts on a big busy street, so almost daily we have to clean up trash from our yard that people in cars (mainly, occasionally pedestrians) have tossed in our yard. That's not only littering, it's property rights violation. Would they toss their trash in their own yard?! (I don't know, maybe they would...). The worst thing about it is that there is no grocery store, gas station, convenient mart or anything, within a couple miles of my residential neighborhood. They had to buy their trash somewhere else and bring it with them to toss in my yard.
But even crazier is when I am out in the woods, sometimes in some pretty remote areas and find beer cans that people packed in with them and left behind. You come to that spot because it is so beautiful, and then you leave it uglier for everyone else? If you can carry it in full, you can carry it out empty!
I'm sure you inspired lots of people's rants here, tom!