Thank you for setting this out. It resonates. Particularly your thoughts about empathy for the jerk. But there’s one exception - about rudeness and the class divide. Class and upbringing don’t always figure. They may have nothing to do with it.
People of every class and persuasion have their blind spots and neuroses. Poor people are perfectly capable of dehumanizing others of their own class. It’s as though people at the very bottom haven’t got a perspective on how we depend on each other. People with good upbringing can be rude, too. Intentionally, unintentionally, based on some perceived slight, or based on some unexamined behaviour - more or less as you described.
As an addendum, I am of two minds about calling people out. It is too readily seen as pulling rank, as a provocation itself. Turns out there are other ways of dealing with jerks in a commercial setting. Write to the business about their clientele, for instance.