Why do some authors write under a pen name, when everyone finds out it's them anyway?

Why do some authors write under a pen name when people know it's them anyway? For example, I was looking on one authors website and it mentioned he wrote some other books, but under the pen name. Also, while I'm thinking of it, people know Lemony Snicket is really Daniel Handler . So why does he bother with a pen name? Why would authors pick a pen name, that would keep the anonymous, and then share it with the world that it is them? I don't understand.
 
Back
Top