Frustrating Ebay Sellers

I use ebay a lot, both for buying and selling. In my searches, when I notice a listing with an incorrect description or title, I sometimes like to let the seller know that way the buyer gets what they are expecting and the seller doesn't get any backlash from the buyers.

I just spent two days arguing with a seller who had advertised a 2003-S Silver Proof Kennedy half dollar PCGS PR-69 DCAM, but the picture showed a graded clad half. I even checked the PCGS item number to make sure my thinking was correct. I just wrote him to let him to know that, unless the holder specifically says that it is silver, it is not silver. He kept arguing back that all proofs from that year are silver.

I ended up sending him pics from the PCGS Price Guide iPhone app that shows both, and explained the PCGS item numbers, and a pic of a listing that had both for sale, but he still argued with me.

It's just frustrating when I go out of my way to try and help him out and he starts yelling and arguing with me. Sorry, I'm just venting as this still has me wound up, but I really was just trying to help him and was not looking for an argument. It frustrates me even more knowing that someone bought that coin, possibly thinking it was silver.