This afternoon I was in Waitrose and picked up a bag of 5 parsnips reduced to 10p from 79p.
When I paid for them at the self-service checkout I realised that the previous shopper, who I hadn't seen, had left 28p change behind.
I pocketed it. I did not hand it in at the counter or leave my name and address and did not put it in the charity box
So unless I am wrong in my calculations, I made 18p out of a Waitrose shopper.