Phones and photography are banned in many Berlin clubs - they either lock your phone away at the entrance or put a sticker on the camera. That's why you barely see any footage from inside Berghain anywhere...
And there are areas in Berghain that are more like a sex/fetish club than a night club.
I've been to parties that have had signs on the bathroom banning acts that would make a vanilla person blush.
[1] https://old.reddit.com/r/redscarepod/comments/11nll0r/my_gir...
The stickers you see on the walls could have accumulated over month. The system usually works fine and you rarely see anyone taking photos. Certainly way less than in clubs without those stickers.