It's not just about having a belief that their economic system is better, these people feel like they're possessed by cult like quasi-religious force, as were past ones like in the cultural revolution. It's the only way the current environment in the US makes sense because it's not logical whatsoever for this many people who grew up in Western countries to think having a revolution and replacing it with an ideology that's clearly failed is a good idea.
Why does this keep happening to human race? What is actually motivating them? Noting that these commies are insanely manipulative and dishonest therefore what they really claim to care about can all just be a front, like arguably the entire usage of race.
I was once told that if something was free, it just meant that the cost was hidden.