Thanks all.
Maybe it's me and litter.
My house in the UK had the lounge windows overlooking our front garden onto a path and I just happened to be at the window when a young man walking by threw away his empty crisp packet!
I'm out the door like a shot, pick the packet up and follow the young man (YM)
Me: Tap YM on the shoulder, proffer the crisp packet and say 'you dropped this'
YM: 'I don't wan't it!'
Me: 'Yeah well neither does my front garden so get rid!'
YM: Was so surprised he shoved it into his pocket looking very sheepish.
Wonder if I was a founder member of the litter police in a previous life?