A disaster in the making...
I use adblockers. But not merely to get rid of annoying advertisements and pop-ups (my browser can handle the pop-ups on its own) but mostly to ensure the safety of my computer!
When I go to a website then I have a good idea what kind of contents I can expect. But it'll always be a mystery to me where the advertisements are coming from. Worse yet: what is going to happen when the source of advertisements gets compromised and starts spreading malware or other virusses (don't try to argue that this could never happen, events from the recent past clearly proof otherwise)?
So yeah, the moment a website tries to force me to remove my adblocker then the effect is very simple: said website will be removed from my favorites list(s) instead. There are tons more websites which can provide me with the same experience, thank you very much.
But back to my initial comment: this is a disaster just waiting to happen. Because what's going to happen when FB's advertising source gets compromised and its proven that FB has (indirectly) started spreading malware and other junk?
Their desire for more revenue could very well lead to their own downfall.