Because they don't want to believe there was ever a need for such an organization. They don't want to know anything about the recent past; they may not be able to complain about being victimized while being 99% of the 1% who owns everything.
Apparently the NAACP has done a poor job of branding itself and telling its story.
Don't know; Don't care.
Yet you cared enough to respond.
Still don't know. Still don't care.