That's got to be a bouncy.
Every store I've been at the past ten years where there's people at the door checking for receipts, and one has made a large-boxed purchase (television, stereo, whatnot), the cashier's always taped it to the top of the box itself, and so one never has to look for his receipt if asked for it. It's right there on the box, for anyone checking to see it.
That includes Wal-Mart in Omaha, Lincoln, Norfolk, Nebraska, and one-time stops at Wal-Marts in Illinois, South Dakota, and Missouri.
Every time.