A bunch of organizations seem to be more consistent adding "Events" to their Facebook page than updating their website, also, so I need to periodically check if I don't want to miss things.

if by 'communicate' you mean 'generate noise', you're right. in other cases, it doesn't matter, they will get to you if they want to. true story.

If there are people who can cut you off for not using FB, that means simply that you are less important to them than they are to you. It means that they are strong and you are weak. Are you seriously going to let such people emotionally blackmail you into using FB?

Situations like yours always remind me of how people emotionally force each other to stay in a religion, by threatening a cut-off of communication if they leave.