You are filing your tax return. By aggressively interpreting the tax law, you see a way you can take a deduction that would save you $10,000. Your accountant tells you that if you are audited, the IRS will definitely disallow the deduction, but that it would be considered a misinterpretation of the rules and not an attempt at fraud, so there would be no penalty or prosecution.
You receive a laudatory performance evaluation at work that gives you credit for several important things you were responsible for, and one important thing that you weren’t. You see why your supervisor thinks you did it, but you didn’t. The person who deserves credit has left the company, so this mistake will certainly go unnoticed, and will do no harm to someone else. It’s a fairly important thing to officially have credit for, tucked away there in the files.
In an antique store, you rummage through a box of 20 cheap old watches. They’re selling for $2 apiece, or $25 for the whole lot. You find one watch in there that is gold and that you know to be worth at least $300. It is clear that the store has no idea such a valuable item has been included with junk, and that if they did, they’d pull it from sale or ask a lot more money for it.
(Note: Generally, a merchant is not legally obligated to sell merchandise at an accidentally mislabeled, too-low price, once the mistake is noted.)