Actually it was concerning, but I'm not a cop and I don't really know what the protocols are when approaching a guy flinging around what appears to be a firearm. And, we're discussing race and not jackbootiness.
Here's another view....
https://m.youtube.com/?#/watch?v=64doDjNg8ts
He walks around the store with the gun, which admittedly looks real, but there doesn't seem to be any panic on the part of any of the other customers in the store. Officers said they told him to drop the weapon, but I'm not convinced he heard them or was even aware of their presence.
Is this due to race? Who knows, but people have been seen with long guns in stores before, and made it out alive. One instance doesn't make it racial, but when you have several events with iffy circumstances, it does make one wonder.