Too bad that NONE of the security cameras that the Security Officers were watching Mr. Scott on 'worked', or we could see for ourselves if it was true.
I have little doubt that Mr. Scott stumbled, was at times incoherent. I know people that have been in the same condition, and go shopping anyway. (though they didn't have a gun).
The bottom line is that whatever his 'impairment' may have been at the time, he did nothing to deserve being shot two times in the front, four times in the back, and one while lying dead on the ground.
With plenty of time to analyze the situation and with hindsight one can say that, but considering what the officers knew at the time and what they observed, they did what they were trained to do.