Challenge the Existence of That Meeting
I once became in charge of a meeting that fell outside of the Scrum canon, so I asked the group if this meeting was useful. I also said that this is our meeting, so we have the opportunity to make this meeting serve us.
'Cause honestly, I didn't want to be associated with a meeting that sucks and is a waste of time.
This is healthy for meetings in general... and I'd argue fully within the purview of Scrum Mastery. I mean, fine, you still might meet, and that invite on your calendar may not change one bit, but at least y'all will be on the same page with stuff like:
Is there a purpose?
Is the purpose understood by all?
Do we have the right people?
Is this the right frequency to meet?
As a Scrum Master, be prepared to answer these questions to justify the gatherings that do fall inside of the Scrum canon. It will make you a better Agilist.
Heck, challenge the team on the existence of these meetings, like a Scrum Master turned evil and antagonistic. It will make the team better Agilists. It's also fun.