It seems that people are increasingly convinced that “in this country it is necessary, now and then, to put one health insurance exec to death in order to inspire the others to pay”.
That is a sign that people believe they can't obtain redress through widely available legal means.
What you are looking at is the people checking the power of the institutions they tasked with providing legal recourse who have mostly been sitting on their hands and/or serving parties other than the people.
If the state, courts and other systems don't get people justice or something you can squint at and call justice when they are wronged some fraction of those wronged will go outside the systems and seek to get even instead.
Public sympathy for the (rare, perhaps crazy) people who shoot CEOs or armor bulldozers are what gives the parts of the institutions that want to do what the people want the political capital to something other than the status quo.
That is a sign that people believe they can't obtain redress through widely available legal means.