Soon there won't be an inch of the planet that isn't being live streamed, whether people are aware of it or not. I really wish Mark had been hugged more as a child.
Not necessarily, you can be holding your phone normally and still film. Especially with cameras with wide angle lenses, you don't even have to be pointing it at it. If you want covert then hidden cameras have existed for decades and continue to get smaller and cheaper. If someone wants to live stream without your knowledge, they're not going for bulky expensive sunglasses.
If you are talking about their phones, they have to be kind of obviously recording, holding their phones up while these glasses may or may not be just passively recording.