I know. I’ve seen perfume on Amazon that normally sells for about $100.00/bottle advertised for +/- $2-5K. The few times I saw it, I just thought they were stupid for trying to sell it for those prices. I can’t find them now, because I can’t remember what I was looking for at the time. I do remember being incredulous.
A lot of these overpriced items are in scarce supply and the sellers know there is no availability, so they jack the price up and have the patience to sit on it.
Many are legit items, especially Amazon books. A lot of booksellers purchase for pennies and can afford to hope for a miracle buyer.