The OP also said that the seller cancelled some sales and incorrectly reported that the buyer canceled. So there’s a second infraction of eBay policies.
The OP may be venting, but he’s also warning us about potential buying issues on eBay.
I just sold a brand new espresso machine finger guard that I took off my grinder before using it. Then the buyer sent me a return request with a picture of the guard with coffee grounds on it. He said it was dirty and used. So I was out the shipping to him, and returning it to me. So there are bad buyers and sellers on eBay.