We were parked at the traffic lights when the passenger in the car in front of us opened his window and gently put his empty bottle of beer on the ground where it was left when the lights changed.

A couple of days later, a car pulled out in front of me leaving a garage. First the passenger threw an empty packet out, then the driver did the same.

Then I found myself following a group of four children down towards Witton Park. They were throwing chips at each other then threw the empty packets into someone’s garden and shoved their half-empty cans into a hedge.

Finally, walking to work one day, I saw a young man with two dogs on a lead in front of me who did not pick up the dog’s mess.

No, I didn’t say anything because of what I might have got in return. What can we do to stop this?

Pauline Grundy (via email).