Our state DNR cut the budget a few years ago and among the cuts were trash barrels at the local park/lake. They still have a dumpster at the main office, and you can dump your trash there (this was confirmed by the manager when I asked), but it's amazing how many people just leave it laying where they eat or fish.
Last week I passed a parked SUV which had a cooler & bag of trash setting behind it on the ground. Didn't give it much thought, but when I drove back out of the park the SUV & cooler were gone, but the trash bag was still there. I think from now on I'm going to snap a pic of the license plate (and the trash) and give it to the park manager if it happens again.
Yesterday evening I stopped to fish (caught a few 'gills & crappie) and someone had dumped the remains from their tub of chicken livers (blood & scraps of liver) on the rocks. No way to really clean it up and not a major environmental issue (the rain last night probably removed all traces), but it sure is unsightly and inconvenient to have to walk around it.