Kind of a niche situation, but I bought a pair of used/demo Renoun Citadel skis during the sale on their website. When I got the box, I opened it up and saw that they'd packaged a brand new pair in there. My conscience got the best of me due to the huge discrepancy in price ($1500 vs $650) so I sent them an email telling them of their mistake and asking what to do. They replied with "That’s awesome of you to point it out but NO WORRIES! We oversold the Citadel demo so chose a lucky one to get a new pair." They definitely won some brownie points with that move.
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