I am SO with you about frustration! I've wasted hours being frustrated, having lots of energy to use but with no direction or outlet. Then for you to attend a meeting where nothing really happens, sure it would be frustrating. I've been to some meetings like that, and if that's they way they usually go, I stop going to those meetings and look for others that are more productive. Obviously, your situation is a little different.
The question is, the group you met with, could they have done something about the issues? And did they just not bother? If they are in a position to take some action, such as writing letters to the church in question signed by all committee members, why don't you propose an action to the group? Or two possible actions for the group to consider? If the group at large doesn't act, see if there was another member at the meeting who seemed interested enough to bring the issue up with you at the next meeting, and propose taking action? Just a thought, if it applies.
But I understand needing to vent, too. Go ahead and vent it all out.