While you are shopping at Costco?
Yeah, nobody could ever pull a knife, grab a blunt object like a hammer, or three or four people ganging up on somebody to strangle or beat the life out of them. Nobody could ever do that at a Costco. /s
Does Costco have a magic force field? I would think anything is possible there that could happen anywhere else.
We all have to forget the “can’t happen here” mindset these days. Crazy people are everywhere. We will need more info to know who the crazy one or group is with this story.