My mum used to make us rub margarine into bruises, apparently it would ‘Make the bruising come out’. This went on until we were teens and decided we didn’t want greasy patches on our arms or legs etc.
And if you were taking something back to the shop for a refund, you had to take it in that shops own carrier bag, so if you were taking something back to Tesco, you had to take it in a Tesco bag. It was rude to take it in another shops bag.