Yes, useful to for Government information gathering if your stupid enough to voluntarily use it as a personal diary.
FB follows folks who aren’t even signed up as members
If you click on a FB (or Twitter) link, as a non member or member, your next clicks are then tracked.
Facebook will keep you on, even after you die.
There are a few growing free speech alternatives to the leftist facebook,google, youtube,amazon , twitter monopoly of the internet. Steemit is out best hope if we spread like wildfire to everyone: