I heard how a company in the long past got a phone call from an elder customer: I've got such a strange letter from you. Reception asks what it says. Says the customer: I don't know yet, they're still busy putting it in the hallway. Huh?

It turns out an error was made in a mass mailing, and every letter was sent with the first address on the list. The list was roughly sorted by birth date, so the eldest customer got all of them. Postal office workers drove with a van to the customer, and duly delivered bags and bags of mail to the same address.