I share your pain. I teach Leave No Trace http://www.lnt.org and have appeared at schools, churches, the state fair, the Hoosier Outdoor Experience (15,000+ participants), scouting events, and almost every state park in Indiana over the years. I have no idea how many people I have spoken with... I do know a lot of the places I go to fish are trashed. It is difficult to get people involved in outdoor recreation and it is even more difficult to get them to respect the outdoors when we do get them there. All we can do is keep trying (and pick up the trash)...