When Cecil Sharp was in the Appalachians (1916 - 1918)he mainly collected ballads from women singers. He did collect some ballads from men, but, as I say, the majority of his singers were women. When I questioned Appalachian people about this (in the late 1970's - early 1980's) the most common answer was that "the men were probably away, working elsewhere." I don't know if this was true or not, but it does give us something to consider.