I contacted the vendor yesterday, and they acted surprised to learn about the engraving. But they said they would look into it.
I then contacted Kahr, and they said they don't know anything about the engraving.
The vendor got back to me today and reported that a group had special ordered the guns from Kahr and requested the engraving. Before the guns were delivered, they canceled the order. Kahr then sold them to the distributor as blemished, thus the reason for the low price on the pistol. And yeah, it was a good price. I did buy it for much lower than the current going rate for that model.
I told the vendor I was not happy about the engraving because A) their product description did not mention anything about engraving or that the gun was being sold as a blem. And B) the engraving is meaningless to me. As far as I was concerned, it was just random letters etched on my pistol.
The vendor then offered to send a shipping label and I could return it for a full refund. Or I could keep it and they would refund $100 of the purchase price.
So that explains the engraving.