Can pack formation threads be private?

... This wasn't any kind of attack against NWF. It was a more theoretical question as there's a lot of X wouldn't like Y creating a pack at Z.

At the start of my second paragraph I said "From what I can tell, there's nothing to stop packs from forming solely from private threads and just ignoring any AW threads that other's make if there characters are unhappy with the pack forming." So yes, AW threads can be created by the pack with a grievance but I was wondering as there's nothing to stop those being ignored.