I don't think I have to worry about personal offense. The thing still has the tag, and I think I can get the receipt unless it's been trashed. He doesn't keep track of them and so won't notice if it's gone.
Turn this negative situation into a positive by donating it.
“May all sentient beings be free of pain and suffering. May all sentient beings experience eternal joy and happiness. gate gate pāragate pārasaṃgate bodhi svāhā.”
This. The manufacturer had already been paid by the time the item was put on the shelf.
Return it, exchange it, donate it, regift it.