Sorry to bring back this ancient thread but I am very interested to know about this topic. I know for a fact that a good chunk of those who write Shrestha in places especially outside of Kathmandu are not infact real Shrestha Newars, they might not even be Newars frankly. I don't know why this fascination towards this one surname, but it sure has made many people change their heritage. In Sikkim too where everybody writes Pradhan despite not being actual Pradhans have started writing Shrestha these days. Why? If anbody could care to answer...