Inequality leads to social unrest, because, the people believe that it got that way because of the idea that the wealth was stolen.
You can't make that sort of logical leap. When inequality gets past a certain point there is a perception that people have been enriched unjustly, yes. (by the way, this is nearly always correct) That in no way means that people believe all wealth is stolen.
I come from CA, and I might not have a good sample, but in my experience the idea is not uncommon, but common. Many consider wealth something in excess. They don't see their cell phone, or car, or trips out to dinner, or makeup ect as wealth. The word wealth has lost its meaning in culture.
I mean I lived in CA for almost ten years and I never once heard someone think of wealth as something that was fundamentally in excess, nor did I ever hear someone say that they believed wealth was only gotten through theft.
Like zero times ever. I think you may be reading into what people are saying a little too much.