If people feel that inequality undermines the social order, they are entitled to do something about it.
Sure. But if they're proposing cures worse than the disease, we should try to talk them out of it, not just play on their feelings of "unfairness" to win political battles.
Fundamentally, wealth can only be created against the backdrop of social order. If you gave Zuck $10 million, far more capital then he started Facebook with, and sent him to Somalia, he would not be a billionaire today. He would've been killed and his money taken. Any business he built would've been taken from him. Because he's not skilled in war, and without social order that's the only skill that matters.
Each person equally contributes to the social order, and therefore each person has equal say in the structure of that society. That's the basis for liberal democracy. If people feel that inequality undermines the social order, they are entitled to do something about it.