How do the Brotherhood recruit new members? I mean, in Fallout 1, you only get "accepted" by them because they need you to do stuff for them. I get the impression in both Fallout 1 and 2, that they only grudgingly agree to have anything to do with you because you're useful to them. And even then, you're only ever more of an "honorary member" than an actual recruit. And it can be assumed that you're probably the most outstanding person in the Wastes - if they won't recruit you; I can't imagine they'd let anyone else in, either.
So that's what I'm wondering, then. They have to keep their numbers up somehow - so how does that work, exactly? (This is something where I've probably just not paid enough attention when I was playing through them, and didn't pick up on it...)
Do we even know, necessarily?