Originally Posted by BendtheBar
There is huge money in knowing what you "Like".
Notice most ads on web pages are catered towards your interests. Google is in on the tracking game.
I use FireFox with Ad Block Plus as an add on. I haven't seen much in the way of internet advertising in years. When they do figure out a way to creep an add onto a page, I just click "Block" and it's script gets added the Ad Block's filtering system.
Facebook and Google are definitely all about understanding your habits to see you things (well, they make money selling advertising space).