For those of you who have considered the "buying fans" approach [or are interested in the discussion of it] Facebook has been removing accounts and revoking page & app likes that come from fake profiles, malware, hacks and other illegitimate approaches. We're not talking small numbers here or there either; the impact to busy apps has been near six-figures [you didn't really think 15 bucks was getting you 25,000 real people, did you?].
These newly improved automated efforts will remove those Likes gained by malware, compromised accounts, deceived users, or purchased bulk Likes. While we have always had dedicated protections against each of these threats on Facebook, these improved systems have been specifically configured to identify and take action against suspicious Likes.
Combine this with the negative impact from inactivity to EdgeRank and I think you'd be hard pressed to find a reason to grow be buying another fan. Agree, disagree or think you were unfairly hit? Chime in.