Wow, that was a pretty quick shoot. looked like they hit him with a rifle as soon as he reacted to the first verbal challenge. I agree there was no time to respond to commands.
My first assumption was it was a scary guy with a gun call, but I didn't hear anything said that was completely untrue though probably exaggerated. Sounded like he mistook him for a potential robber and didn't recognize the pellet rifle his own store sells. He never got real close in the footage shown. I was much more shocked at how quickly the police resorted to shooting him. Not what I would expect.