I grew up in a time when it was not a total panic situation to see a guy with a gun. When I saw a guy with a rifle it was not my first thought to kill him. It is not the gun that is bad. It would take some kind of indication or action that the person with the gun is bad.
When he first steps out of the bathroom the rifle is not pointed at anybody.
(Some of you would shoot him, I wouldn't)
So the guy had to first point it at somebody, that is an action that indicates the guy is probably a bad guy. This state of affairs is not particularly interesting because this state only lasts a fraction of a second before he actually fires the rifle. Now the situation is clear.
(All or most of us would shoot now including me.)
When he first steps out of the bathroom the rifle is not pointed at anybody.
(Some of you would shoot him, I wouldn't)
So the guy had to first point it at somebody, that is an action that indicates the guy is probably a bad guy. This state of affairs is not particularly interesting because this state only lasts a fraction of a second before he actually fires the rifle. Now the situation is clear.
(All or most of us would shoot now including me.)