From John N. Berry III, Why I Stick with ALA:

“Most important, ALA provided an open structure in which members could organize units to advocate for the information rights of women; gay, lesbian, bisexual, and transgender individuals; the incarcerated; the poor and homeless; indeed every citizen. That structure allowed activist members to force the old association to be more democratic a few decades ago.”

Whatever your thoughts on the structure/bureaucracy of ALA, Berry has this part right: it provides an open door for new, underrepresented, and/or marginalized groups to have a place and a voice.