Do you have any actual examples of C&Ds or lawsuits in this regard, or did you just mean they might ban the users/your account? The latter is pretty expected and tame, but it'd be surprising/interesting to look at actual examples of the claimed.
Being banned from Facebook would be a VERY big deal for many users. If FB is willing to ban users of the extension (however they detect it), usage will drop to 0 fast.
