Chest of Gems
When I was contracting, sitting next to another older colleague - a parent of 2 - we had the funny experience of him shouting out one day - after noticing that Apple had sent him a bill for over a hundred pounds, including one purchase of "£69.99 for a chest of gems" (googling, I've found it was game: Skylanders Lost Islands).
Pointing out that this was just a "recent" receipt and his children may have made more purchases, I showed him how to look up all your "past purchases". To his horror, his children had bought another "chest" previously - adding up to a lovely £140 of in-app purchases.
He wrote to Apple explaining the situation - and to all our surprise, they actually responded back with,
"Here is the money back sir, but rest assured, we won't be giving you the benefit of the doubt next time...".
Well done Apple (lol - but for our enjoyment, well done his two clever children in the first place ;)