So many people have so many problems, complaints and grievances and "the system" as it is almost everywhere on earth is corrupt, violence prone and sclerotic it is inevitable that you get some violent eruptions. That's why everyone is being spied on!
So that you get these isolated incidents, - easy to contain, easy to discredit - given that no grouping of any size can make any sort of clandestine plans. And also given that actual on the street protest is criminalized unless POTUS wants it to be like in Kiev or Caracas.
Walmart can serve as a symbol or metaphor for much that is wrong with the world today. Probably that's why this drama played out in s Walmart store.
I hope they left a manifesto of some sort and if they did that we all get an.opportunity to read it.