Are you obligated to give a refund after an item is lost in the mail

[JollyElm]

I buy a lot of stuff off of ebay, but usually just lower priced cards to upgrade my sets, so I welcome PWE's if it keeps my shipping costs down. A while back, I didn't receive a card in the mail (not sure if it was a PWE or 'regular' shipping), so I followed the proper channels through ebay and got a refund. However, a long while later, out of nowhere, the card eventually showed up. We're talking a month or two later. I messaged the seller, told him the package arrived, got his paypal info, and paid him again. There was no bargaining or throw-ins required. I just did the right thing. Hopefully that's what other people do, too.