Stop having pointless meetings
medium.com
medium.com
In that case, do the following:
* At the beginning of the meeting, do a check-in. Everyone says what's different after the meeting has been finished successfully — preferably in one sentence.
* At the end of the meeting, do a check-out. Everyone says whether the meeting has been successful for him and, if not, why and what could be done differently next time.
It's also helpful to include your personal mood or things that block you from contributing in the check-in. This helps others help you in getting the most out of it.
Last but not least, if the check-in reveals that someone is not needed in the meeting, double-check if that's really the case with the team and then let him/her leave.
While the former is still unfortunate, it can easily be taken care of within the meeting collaboratively. The latter is harder to come up with in an ad-hoc fashion, but it's still possible.
I agree that in an optimal world, every meeting is planned appropriately beforehand and meetings that aren't necessary do not exist. In reality, that's not the case. So you have to deal with that.
Just complaining will not help.