I think a lot of them do "get it" if by that you mean they get that the "trooth" is NOT the truth.
Lotsa reasons to stay in the borg that has nothing to do with really believing in it. I beleive that for many, they simply lack the courage to disengage from the pain that is familiar and jump into the unknown. Many people stay stuck in marriages and jobs that they hate for the same reasons. Throw in the notion of being a big frog in a tiny pond - and it is really not that complicated.
An interesting question would be - of the 6 million, how many really and truly believe it? I felt for a long time that if Armageddon ever really happened, JWs would be of the 'Most Surprised' class.................