Interesting observation. I would only add that the adage, Forewarned is forearmed, is appropriate here. Not only is there value in recognizing that there may be perceived bias going into an interview, but also being aware of what that potential bias is and how to a.) avoid finding yourself in an adversarial position with the reporter, and b.) leveraging that bias in your favor.
For example, if you know that a given interviewer is very much in favor of reforming healthcare and advocates single-payer (and you do not), not only should you be careful of what you say to the contrary, you can shape your message subtly that will gain favor with the reporter’s natural bias, without overtly disagreeing with his or her position. It’s careful treading, but you should at least know going in who has the pen, and who buys ink by the barrel.