Marketing that which does not need to be marketed

I have always wanted to do one of those dense, integrated campaigns that seduces consumers with mystery. I tried once, but the effort was just a stopgap measure performed on my own time and creatively it was a huge flop. The marketing supporting the film of Watchmen is just the sort of thing I wish I could have pulled off. Microsites, games, coffee and much more. But I wonder why one needs to do viral marketing for this film at all. The director of 300 helms the film version of the greatest graphic novel of all time? That's going to get attention from every theater, website, movie critic and entertainment show in the world. And my guess is that the sort of people who use their iPhones to play online multiplayer games are already going to see this film anyway. Maybe they should have spent their budget on TV?