I'm not sure if this qualifies, but I have a friend who way back when, like decades ago, probably before the extensive surveillance we have now, would do something rather ingenious and devious to get major discounts on whatever expensive things he wanted at stores: he would print out a sheet of barcode stickers for a product that was similar but much cheaper than the one he wanted and plaster it on a bunch of the items like the one he wanted. Take it to the cashier and get a super discount.

For example, if he wanted some fancy model of an electronics gadget, he would print barcodes of a much cheaper but similar model from the same manufacturer. According to him, he had even done this for fancy cuts of meat. The reason for applying it to a bunch of them and not just the single one he planned to buy was for plausible deniability. If someone questioned him, he could say, I don't know, I just picked one off the shelf - they could go check and see that there were many labeled as the cheaper item.