To your point: "Just shoot the guy in the leg, that will stop him"
And the phrase "that stuff is from movies" is ******** .
In many other countries police are trained to IMMOBILZE a target and not to KILL it, they're trained to shoot at non-vital points of the body and only to shoot in absolute need.

Then again, in the US nearly everyone can carry a real weapon, so I guess the danger is bigger there.