My understanding is that the tenants on the land belonging to the landowners took the landowners name as most people of the period had no last name. Most people with the name Frazier and its variants are not descendants of Simon Frazier. It is one of the most common names in the English language. My mother was a Frazier from Granville County. We think they were Scots-Irish, having moved from Scotland to Ireland and coming to America from Ireland.