To me it's like team spirit. It's just plain foolish and counterproductive to belong to a team and not support it.
Get in there and work for change but don't end up being part of the problem in the process.
Break it down to a microcosm: A household. If you can't live there and be part of what keeps the house up and running, move over and let someone else have it. Find something better and work at that household.
It almost strikes me as a national trait of low self-esteem to belong to something and then do nothing constructive but continue to bad-mouth it.
Evokes thoughts of Groucho. "Any club that would have me as a member I dont want to belong to." Hee.