From what we saw of the group during meetings at Emily’s, they were made up pretty exclusively of middle aged and elderly corporate wives, not young women just getting their start in life.
The character had always been dedicated to whatever task she set her mind to, so that wasn’t the issue, but she was brought up with more middle class values than the what the DAR represented.
Rory threw herself so fully into the DAR and life living in her grandparents’ pool house that, to many fans (and certainly the character’s mother), she hardly seemed like our good, old reliable Rory any more.