Where did that chair come from?

Have you ever noticed trash on the side of the highway? Recently, I've seen a wooden chair, part of a mattress, and a hitchhiker. Obviously I'm not surprised to see regular trash on the highway i.e., cans, wrappers, bags, etc. However, I can't help but wonder who is throwing out a chair? Seriously, who is driving at 60 mph and thinks to himself, "you know what, I think it is time to ditch this chair. I'm just gonna toss it out the window." Who does that?  Well clearly someone is doing it because I notice random pieces of trash all the time.