Why is it that you never come across anyone with the surname 'Hitler' nowadays? Am I correct in assuming that a lot of Hitlers changed their name as it became associated with the Fuhrer?
Hitler as a name seems to be an invention of Adolf's father, Alois. Alois was born Alois Schicklgruber. Later his mother married Johann Hiedler. When he was 39 Alois wanted to associate himself with his step-father and had his name changed. No one knows why he chose the Hitler spelling rather than the more traditional Hiedler spelling.
So the Hitler surname was pretty limited. And once Adolf was done with it, most everyone who had it changed over to Hiedler, Hütter, or swapped it out for something else completely.