How is email even remotely comparable to FB use?

It's not even addictive.

This is like saying you taught your mother to enjoy mint-flavoured soda water ("a glass of water is just as good for thirst") ... as a way to defend having to drink alcohol to feel accepted by your friends.

Oh and in a lot of cases, the fear is not even real, you just believe you need FB. Your friends might just surprise you yet.