Or perhaps your Facebook friends had their own accounts randomly hacked and phishing messages were sent to every one of the account's Facebook friends.
At any given point in time, half of America is posting some sort of critical message about the government online.
So that was my first thought. I accused them of carelessly falling for phishing and other stuff. But they had not seen any emails from their facebook friends or any other phishing attempts. And it seem like I was being targeted by various different facebook friends. Which increased the odds of me being the target.
Facebook plays fast and loose with data, perhaps one of your friends used a FB integrated service at some time which captured their friend list (e.g. you).
At any given point in time, half of America is posting some sort of critical message about the government online.