things seen out a study room window

[huskyprof]

A older man stopped his pickup in front of my house. He gets out, kicks some debris, and gets back in the truck. He drives about twenty feet more, gets out, and picks up a aluminum can from my forested yard. He takes the can, pours out whatever was left in it, and throws it in the back of his truck. He drives another twenty feet, stops, gets out, and picks up another can from my yard. He looks at the can for a moment. This can does not interest him. I know this because he flings it back into my front yard. He gets back into the pickup truck, a well-kept one with nice blue paint and of recent vintage, and drives away.

Why?