Experienced rather than overheard. Some years ago was working in Ireland - pre Euro -went to the local supermarket but didn't have a punt for the trolley. Saw a couple returning theirs so asked the woman if I could give her two fifty pences for her trolley. She said OK, parked the trolley got her pund out and swopped it for my 2 x 50p. Even her husband was left shaking his head as they walked away