This style of activism is harmful to the cause. No one in that restaurant is going to think “Huh, those people had a point. I will consider their message more.” They’ll simply resolve that vegans are crazy and annoying, and be pushed further than ever from converting. Honestly shouting like this is just performative for the people doing it. The best ways to be an activist imo are engaging people personally (like Earthling Ed’s good-faith debates) or even just presenting people with information and going for numbers, relying on people engaging in self-reflection on their own.