So I'm exiting the train to go to work and this guy reaches into the trash can, pulls out a recently discarded Coca Cola can, bites it, tears off the bottom and throws the carcass on the floor of the CTA station as he walks out. Disgusted, I declared, "What a jerk!"- but only loudly enough for the guy next to me to hear. I picked up the remainder of the can off the floor and followed the guy out to the street (we happened to be walking in the same direction, I'm not that insane) and proceeded to imagine a scenario in which I yelled, "Hey white shirt, I believe this is yours!" Then, waiving the can indignantly, I'd toss it in the nearest trash can and deride him further: "Don't litter, it's detestable," as I walk away, scowl and all.
In reality I just threw the can away and went to work.