What are people on nights truly doing? (I.e. night guards on Facebook)

There is a whole community of people on nights, and I just don’t get it, before i deleted fb i had a few night guard friends and they were all just posting videos of people coming in and out of the area.<br><br>What’s the point of that? It’s like sitting in a mall and filming people walking in and out! <br><br>I’m guessing it’s that there’s an element of danger to it, like some crazy stuff might happen? But why does it have to always be a night guard?