That's nonsense. You're saying that everyone should just sell anything they own the first time they receive an offer without doing any due diligence, or verifying that the offer is even fair? If I walked up and offered you $10 for a painting you owned because I knew (but you didn't) that it was actually worth millions, would that be fair? But according to your claim, I should be perfectly justified to be insulted that you would even want to find out how much the painting is actually worth before selling it!