Scammers don't typically unfollow people who are following them, since it increases the likelihood of those people noticing and unfollowing back.  They want you to stick around and learn how to get rock-hard abs in your sleep with a patch.<p>Twitter accounts are blocked from following too many people if they have a high follower-to-following ratio, so in order to have a large audience, you have to keep this ratio closer to 1.<p>An 'internet marketer' will follow many people in an automated fashion.  Some will follow them back - either automatically, or because the scammer is convincingly faking a real person.  The ones that don't follow them back are useless to the scammer.  He therefore needs to unfollow them - so he can drop his following-to-followed ratio and begin the cycle again.  SocialToo (and many other tools) help with this by automating the unfollowing part of the process.<p>Promoting scammy affiliate offers through Twitter only scales to an interesting point through automation, so if you break the automation, you break the process.  That's what I assume Twitter is doing.  The scammers will eventually replace API-based methods with screen-scraping bots, which is what they use for other social sites around the web.