Any celebrity who visits the campus (recent drop-ins include Kevin Spacey, Michelle Pfeiffer, Billy Bob Thornton, Ron Howard and Willem Dafoe) is immediately suspected in press accounts of canvassing residents for their Academy votes. It's a sexy angle, but a wild exaggeration. There are, after all, about 5,500 film professionals who determine for the Oscars each year. About 15 of them live at the Motion Picture home.