I agree with Crazyguy, well observed Menrov/Michel.
In the main Jehovah's Witnesses are indeed a social club-- who really cares about doctrines? Doctrines are like an exclusive wallpaper decorating the clubhouse walls. It takes courage to resign from a social club which you know will ostracise you when you leave.
Human nature dictates you do the things your friends do for the sake of solidarity with them, for some people even if it means defending unreasonable ideas. Friendship and identity are important factors for a stable mind. It just happens that the JW doctrines and culture are not only defective but actually deprive people of their natural right to choose their own satisfying path in life.
By devoting their time and energy to the cult, JWs remain dependent on it, just like children are to their parents but permanently so-- and they lose out on personal development, ending up poor, disappointed and unfulfilled.
The promise of paradise looks too good to miss! If only those, when they were contemplating joining the religion, could know how it really ends: it does not end in paradise.