(business cards; from my office wall)
One of the reasons that publicists and marketing people exist is to be an intermediary between authors and the outside world. (Unrelatedly, this is also why people have FAQ sections on their websites.)
When media that wants interviews or bookstores that want events and they need to get in touch with an author, frequently it’s easier just to get in touch with a single publicist with whom the media or the store already has a relationship and talks to on a regular basis than to e-mail a different author every time a new book comes out.
This can also be easier on the author’s end, because rather than having to respond to e-mails from lots of individual media outlets saying, ‘I’m definitely up for an interview — send me questions!’ a publicist (having already established that the author is up for doing as many interviews as possible) can deal with that aspect of things and just give the author a direct shortcut to the questions so they have more time to spend on making some books.
It can be a weird and complicated situation for media, bookstores, foreign publishers, etc. to figure out who to e-mail about professional inquiries if there’s already a personal relationship — do you talk to the author (who you know) or to the publisher (who you also know)?
We tend to lean towards always e-mailing the publisher, because a) we like to know what’s going on, b) with most of our authors, we’ve already had extensive conversations about the kinds of things they’re interested in doing to promote their books, so we’re fully informed, and c) we’re also employed to sit around and e-mail people about our authors, so we’re generally around 9 to 5+ five days a week doing just that.
And that way you can save your author-contacts for ‘I loved your book!’ letters and photos of delicious ice cream and cute kittens (always good things to send authors you like) rather than having to bug them about what kind of AV they want at their event and whether they’ve remember that their interview questions are due tomorrow by 9am.