When I was 17 I acidentally over pumped $5 worth of gas. I panicked because I didn't know what to do when a really nice lady came over and asked me if I was ok. I told her and she handed me $5. I asked for her address to repay her and she no she was happy to help. So nice of her!
Small but I almost always leave my quarter in my cart from Aldi for the next person.