I mean if I come along, submit my site, and automatically go to the front page where I then have to be removed if I'm bad, then it will attract every spamming jackass out there with HN open in one window and AdSense in the other.
Perhaps an alternative might be reducing the amount of upvotes that a 'review my startup' post requires to get on the main page in the first place. Or perhaps some combination of the two.