That, or I was thinking this wasn’t even real, and was more of a “proof of concept” video with the ads edited onto the buildings. So, the person would have to stay still to make it easier to overlay the animations onto the building without having to worry about the angle getting messed up and making it too obvious when the angles of the animation and of the building’s face don’t line up.

I don’t really have any definitive proof of that, though, so it’s honestly only a guess