It doesn't surprise me, Jim. But you can console yourself with the thought that it was probably from some old person's collection and was found while cleaning out their house. Texas, as you well know, has large areas that were founded by German immigrants, so it wouldn't surprise me that this disc was in someone's collection (and was circumspect enough about it that they didn't want others to know they had it).
If I had found it at a garage sale, I would have bought it just to have the pleasure of breaking it.