That stinks. I've been shooting across from MacGregor lake and found piles of trash there too.
I think it has to do with people who feel entitled or are too lazy to clean up after themselves. You see them at my club, people of all ages leaving their brass all over the place, as if their trash had value to others. (in the case of brass, it does)
Here in the PNW we have a non-profit group called
Trash No Land. They have organized dozens and dozens of cleanups of shooting areas in OR and WA, and work with DNR from both states to set up official shooting areas with backstops, berms and parking.
I've been to a few. Great people, camaraderie, cookouts and shooting afterward, and lots of fun to be had.
Also, when I head out to the state or national forest lands to hike or shoot, I try to bring boxes or trash bags to pick up the inevitable heaps of trash that slobs leave behind. It's pathetic.
I encounter numerous areas while out where people have dumped off anything and everything. Tires, trash, pallets, plywood, old appliances, construction debris, a roof in one case. You need a front loader and dump truck for some of the junk these m'fers leave behind.
Then you get into the areas where people are living off the grid, in a lawless fashion. We call them "fringers."
Pizzes me off.
People I know will question why I will stop and fetch a shopping cart on the side of the road and deliver it back to the store it came from, a few miles away. Just the right thing to do.