I have the same problem with my husband's line of Stamms. I think the reasons stated are all right ,plus when people ask ,"who are your people ?" and we reply in the plural by adding that s ,then it sometimes sticks. I am constantly amazed by the people who answer queries with the reply-not my line we don't have an s.I honestly think these people haven't been doing family research for too long to not know these spelling things happen all the time.I spent years looking for a grandpa Alonzo Moore only to have the Urbana Free Library tell me his name was spelled Elonzo for the first two census records he appeared on. Nothing , even when written in stone in this area can be the last word. Emily Adams Matthews