First, GGRM wasn't a part of that event. Second, most organizations wouldn't tolerate or permit Ron Vane's actions unless GGRM and the host organization were both participants of the event in question or had already agreed to allow him to hand out brochures; again, GGRM wasn't a participant, and it's a safe bet that he didn't have prior permission from the PLA if its members were annoyed.

As John said, the PLA folks didn't want to create a scene in front of the passengers by kicking Mr. Vane out; chances are he was well aware of this (and probably the GGRM "leadership" as well) and he therefore took full advantage of the situation.