because they’ve been taught that life is a zero-sum game: if anyone else’s life improves - even just a little - it must necessarily come at the cost of someone else’s life getting worse. this isn’t true, of course, but they can’t see life as any other way, so the ideas of equality and working together to improve society are antithetical to their worldview. they’re to be fought. They have an “every man for himself” philosophy, and it’s nothing but selfish, self-centered solipsism.