The "Like" button is the "Honk if you..." bumper sticker of the data highway. It doesn't represent an opinion, it asks for one. "One" is the keyword, it's rudibinary. There's no freedom of choice, not to honk/like means automatically "No". It doesn't matter if you are neutral and have no or an analog opinion. Or more simple "You're either with us, or against us", read about that pseudo-logical phrase here: [link]
This dogma is the plague of the web, just think of "Don't like, don't look". The data highway becomes more and more an one-way road to hell. Now it's your turn, will you fave this or will you write a comment? Or will you print the PDF and stick it on your car?