It didn't stop Elton John (Reginald Dwight) or Mark Twain (Samuel Clements) or any number of others from appearing in public or doing signings. Personally, I'll be using a pen name because my name is already in use by an ex-police chief in Calgary, a country singer in Alberta and the ex-CEO of a fortune 500 company. It used to be just me with my name on the Internet. Now a search turns up everybody and their dog.
Good point, and my publisher mentioned this as a reason several of his clients took on pseudonyms: existing established authors in the same genre/market with an identical name. Bringing out your middle initial just isn't distinctive enough. Another reason she mentioned is internationalization and language limitations. Employer aside, this is another reason my publisher is comfortable with my decision to use a pseudonym: nobody can spell my name for trying. It's Gaelic, and hard enough to pronounce, much less spell. She has proposed transliterating my English pseudonym into any foreign languages (such as Urdu, Cantonese, Hindi, Punjabi) as required, and I'm fine with it.
Dang... all this fuss over a name. Careers ending, seedy ventures, publishers abandoning you... I guess that answers the old question: what's in a name?