Shopper club cards might be part of an Orwellian masterplan to scrutinize your purchasing habits, but they also have another, less well-known use. Zach says that after an evening of drunken frolicking around New York, he lost his keys. A month later, this showed up in his mailbox.

Someone had found the keys and dropped them off with A&P, who tracked down Zach using his shopper club card data and mailed them to him. He was very grateful, writing, “I thought it was a very nice gesture on their part.”

Turns out this is pretty standard practice, most club cards have a notice on them that says “if found, please return to” (the supermarket they’re from). Nice to know that it works.

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