Be Careful What you “Like” on Facebook:
Once the page creators have piled up hundreds of thousands of likes and shares, they’ll strip the page and promote something else, like products that they get a commission for selling. Or, they may turn around and sell the page through black-market websites to someone who does the same. The “new” page may be used to spread malware — or for phishing,
See CNN article: http://www.cnn.com/2014/01/21/tech/social-media/facebook-like-farming/index.html?hpt=hp_c3