My dear Aunt Ruth was the youngest daughter of a lady (her grandmother, my great-grandmother) who was the youngest of 11 children. Our ancestress died very young and had not imparted any family knowledge to Aunt Ruth, so that that branch of the family was cut off (my grandfather died years ago). Aunt Ruth did not even know her grandparents' names. I got started on that branch of that family and was able to provide for Aunt Ruth before she died the names of her grandparents, where they were born, where their parents came from, and quite a bit of interesting information about them, including the names of all their children. She told me she was so happy, that she had always wondered who they were!
It is very much a Southern thing to know where your family hails from. It is also necessary if you want to join the D.A.R. or the Daughters of the Confederacy. We aren't descended from a "Signer" -- but we ARE descended from the brother of one - the elder brother of George Walton, who signed for Georgia.
The same goes for the S.A.R. or the S.C.V., of course.
I joined the SAR on the basis of descent from a member of the Virginia militia who was present at the siege of Yorktown. I don't need to know that I had an ancestor who fought in the American Revolution, but I find it interesting.