Yeah, if someone pays you real-world money for a micro-transaction, you really need a record of that. Maybe not the pixels themselves, but at least a reciept for what items were bought so you can hand them out again later. Even a bank account statement for what people paid you would do, if you can process it.
And you need to guard that information with your life.
Because telling people, "Oops, we lost your stuff, feel free to buy it again, though," is a QUICK route to bankruptcy. If not having an angry mob outside your door.
