nope. again, if the standard were up to you any player could call anything you do griefing and have you banned but thats not how this works at all, something that has been made clear by blizzard both explicitly via statements and implicitly by the fact that said NPCs can even take damage from players.
i think this weekend will be a fun time for some 40 man raids on capitol cities.
hopefully you werent planning on doing any shopping 