You have to keep in mind that you have to share and post a lot (!) when you take part in Facebook campaigns. So you are spamming others Facebook walls and a lot of your "friends" will unfollow you.
that is true . some people say it's just rubbish, for people who do not really understand bitcoin / facebook campaign. i experienced it, my friend was initially 5000 but after i got into bitcoin world (facebook campaign) my friend poked (decreased) every month