Having the right to shoot one and doing it are to different things. I have seen police here in much more dangerous situations. And they would have being justified in using lethal force but diffused the situation without shooting the offender.
Shooting should be a last resort. It didn't look to be in this case. Maybe the police are better trained here.
What the police here come up against without resorting to lethal force in link below.
www.youtube.com/watch?v=P3UwgtrsqGo