Even if they received a more valuable relevant item.
I always evaluate a sellers feedback before I make a purchase, and I noticed a buyer who held a grudge against a seller for a very cheap item.
The seller purchased one Pokemon Trading Card Game card for $1.50 (including shipping and handing), and they left negative feedback because they received "items" they didn't order. That seller only sells Pokemon cards.
I've received the wrong trading card item in the past that was more valuable than the item that I ordered, and the seller offered to refund me if I send the item back, or keep the item.
I opt to keep the item that was 50 percent more valuable, and I gave the seller positive feedback because I scored a sweet deal...