I think the only reason that he had so many names was because he was a well traveled man. And with all the different languages and cultures in Middle Earth, the names were just bound to stack up
It is funny to see all those names. I wonder if he would have ever gotten confiused. Like someone would come over and say "Hello Strider", and he would like be "That's not my name! *thinks* No, wait, *thinks of the list*, yes it is, sorry" So many names, so little time
The only thing I am wondering about now is that did people in the Middle Ages, or the long gone past have a giant collection of names like Aragorn and Gandalf or was it just a Middle Earth thing?