Question about a seller

I recently purchased a collection of books from a seller and it seems the seller has to pay a lot to ship them to me. On their listing the shipping was free. Anyways, he’s throwing a fit because he’s not going to make any profit on the sale, he’s going to retire from eBay etc. he’s laying it all on me. I’m not obligated to send him money to cover costs right? It sounds like a dumb question but the shipping was free and I paid quite a bit.