I would liken it to a hole appearing in your roof (the roof in this case being your good social behaviour), whether the hole is created by a person or the elements you still should fix it, rather than saying "nah, because that guy made the hole I'm not going to fix it."
If a hole appeared in my roof it would get fixed as it affects me so it matters not who created it. This situation was caused by two outside parties and i got caught in the middle of it. Man drops bags and purposely ignores them, and a woman who has a problem with the bags on the floor. Nothing was my doing i just got caught in the crossfire because i was immediately next to the crime scene
I did nothing wrong, maybe i did nothing right, but i certainly didnt do anything wrong.
The old woman had no right to have a go at me, she was in the wrong, her problem was with the guy at checkout who dropped the bags and ignored them
He made a mess which he watched fall to the floor and walked a few feet away from and then stood at checkout, me not bending down to tidy up this mans mess whilst he stands there doesnt make me his bitch and is not bad social behaviour, the old woman shouting at me for it is bad social behaviour as was the mans who made a mess and ignored it