A thought:
There are black chantey singers. Here is one group:
http://www.coresound.com/fa-menhaden.htm


I wonder if the proportion of Caucasian Americans who know anything about chanteys/shanties is any higher than the proportion of blacks. I remember a review of Johnny Dep's CD after the Pirate craze began. The reviewer suggested that someone ought to look into the history of shanties as if Dep had discovered something new.

This type of music holds limited appeal to a limited number of people. Struggling Maritime festivals prove that out.