They're still used goods. It's very unlikely that the still better-quality goods aren't free of blemishes or marks. It still involves dealing with someone that isn't going to give you any kind of warranty in case of an issue, or that might only take cash, etc. There's also a huge assumption on availability of those used goods, which you cannot guarantee.

Sure, there's nothing wrong with all that necessarily but it shows that it's not an apples-to-apples comparison. OP's statement isn't fair by saying that Ikea is just as expensive as good quality wood furniture.