I think that the policy of enforcing Google's nofollow guideline by removing sites from their index is not directly about keeping their index free of spammers. It is about enforcing a standard for disclosure specifically designed for their purposes. It's not about disclosure to users, it is about disclosure to search engines.
I don't want anyone purposely deceiving the search engines. I have a problem with the way Google is enforcing this. I think this hints at the issues with having such a powerful Google.
