I'm rushed, too, after all. After over a hundred interviews, there really is nothing left that I haven't been asked. No journalist in his or her right mind would sit down with Ruth Rendell and ask her what she thought of Murder, She Wrote, but many journalists seem to think talking about Star Wars or The X Files is somehow germane to my work. A journalist is supposed to be impartial, but all that training often seems to go out the window when talking to an author about a book. But they're constantly telling authors their opinions of the writers' works.
Authors are different to interview because they are trying to sell a product.
They're already in the public eye, and have already got a prominent soapbox, often more permanent and enjoyed by a bigger audience than the work of the journalist interviewing them. On the other hand, because authors are, by definition, good with language, they are often very easy interviews, offering up great quotes or sound bites in profusion, and usually knowing exactly what the interviewer needs to make the piece work, so that the interview can often be conducted in less time.