Because a friend just sent this one to me. You have to listen to this a bit to get in the groove of it. Once you listen for a minute or so, you are drawn into it.
Give it a chance. You may have heard something similar if you watched the movie Cold Mountain, but it was much "cleaned up" for the movie. Real Sacred Harp singing is very unprofessional. Sung from the heart. I love it, but it's not everyone's cuppa.
NOW it's off to clean the refrig!