I used to see this kind of behavior in the NV desert..made me crazy! Even here in CA around the Georgetown area, folks will dump their stuff on a "back road" rather than pay a few bucks to take it to the dump!
We play a game riding up there sometimes outfitting our "virtual house" with a hot water heater, a washing machine, a dryer, a chair, a table, etc...along the trail.
I think it may also be a function of the fees to dump?? I really like the community dump days Placer County sets up, usually some sort of non-profit org. does the work, donations are accepted, and the county accepts the trash for free. They take hazardous stuff, electronics, etc.. We have them several times a year in various areas. There was even a high schooler last year who did one as a senior project. The $$ went to improve the recycling in our county.