I think the point here is not that the cashier is suspicious, since they scanned my ID and credit card numbers etc, so in the event of a fraud they'll have plenty of information to track me down. I think they're just curious because, not to insult anyone, but for someone working at a CVS as their day job, this whole MS game is probably out of their reach and would never occur to them to buy money with money to get more money (essentially what we do).