[Non-Sequitur]

Tangentially to this, I wonder if the “possibly destroying merchandise” was the customer simply being klutzy and knocking tightly shelved items to the floor, or knocking them over on the shelf then knocking them to the floor while attempting to set them right, in the larger process of trying to examine items among them?

According to one of the witnesses, the victim had broken open a case of sports drinks and was fitting them into a backpack, obviously trying to find out how many the backpack would hold. His actions were deliberate, and while they may have qualified him as being a bit of a jerk I don't think they were worth killing him over.

[HiTech RedNeck]

Breaking open a box would have been wrong and possibly a reason for Costco to summon their security staff, but many sports drink packs come in plastic yokes, and individual drinks can be slipped out of and back into the yokes. What a tragedy of errors, even if nobody had malice.

[JSteff]

qualified him as being a bit of a jerk I don't think they were worth killing him over.

That is enough reason for the storm troopers. Remember, it might have been a slow "assault" day. No scheduled Ninja suited raids, no warrant-less home invasions, so what the heck, lets waste someone.

[Hot Tabasco]

According to one of the witnesses, the victim had broken open a case of sports drinks and was fitting them into a backpack, obviously trying to find out how many the backpack would hold.

If I'm not mistaken, you have to bring your own boxes or bags or whatever to carry out your purchases......I suspect that's what the backpack was for.