you know what i woulda done (also in the circumstances of stupid driving/parking), i would memorize the number plate of the vehicle, go home and tell about four - five people and call up EPA (friends calling seprately each of course) and say... "OMG, this car just threw a maccas bag out the window and its hit my front windscreen, I've got food scraps all over my front windows and i nearly crashed! something should be done about this kind of behaviour!" "Did you happen to see the registration sir?" "Yes indeed, it was [ENTER HERE]" LOL, of course the same maccas bag can't work on all 5 different vehicles, other stuff works like maccas drinks, beer bottles, ciggarette butts etc. but yeh.. major admiration points to you buddy for keeping your kool, i woulda lost my temper the moment they tried to block my view with their fones lol