>>600581
It's not. If you look at the video the guy always point at the ground zt slight angle in a controlled manner.
It's a warning shot to scare people off.
Firing in the air is arguably more dangerous than on the ground (as long as you know where everyone feet are), plus I can't figure out a way to do it without completely broking stance or basically shooting at hear level which isn't exactly a good idea either.
The reason you keep the gun close to the body when pushing back is to avoid having your arm holding the weapon grabbed which is the most important thing.
It's clearly not something anyone should do, but we're talking insane tier OPERATOR here. In France GIGN can only graduate to operator status after shooting each other with live ammo in vests…