I don’t think they will be doing anything to provoke pepper spray. Anyway, the Meetup people are not going armed with anything. Our police are very used to these events and know how to control them.
Please don't take me wrong but UGGGH! You better damned well be prepared for violence. Bring a helmet and at least a face mask for when the pepper spray starts flying. Personally, I would bring something incongruous to whack any model Democrat citizen getting in my face and not taking "Back Off!" for an answer.