> I wouldn’t be surprised if people wearing these would get confronted, denied entry or beaten up regularly. I can even totally see them ray-banned legally.

I really, really hope you're not advocating for that. That's straight up violence, not in self defence.

Depends on the jurisdiction and circumstances. In my country filming someone without their consent is also illegal. In a situation where someone feels violated in their privacy, when words didn’t work, force may be required. Advocating or not, it’s likely going to happen. Pointing a camera at someone‘s face obnoxiously tends to escalate situations. Mix alcohol, testosterone and happenstances and you got yourself broken glasses. Try that with a phone camera today and report back.