When you are born in luxury, you have to do nothing else in life. All you need to do is to ensure you continue to stand where you are, and others stand where they are(To keep your advantage). When that thing gets disturbed, people feel uncomfortable.
From a poor guy's perspective he has to 'rise' no matter how. From a rich guy's perspective he is supposed to stay where he is no matter how. Most rich people think, the poor are poor because they don't deserve to be rich. And they are rich because of a special gift, like a unique blessing which only they are supposed to have as it was given to them at birth.
This is not just restricted to money. This sort of a thing also happens in many other things like for example born-with talents Vs Gathered skills. Naturally talented people don't like others gaining their skill through practice. Because they feel their born-with skill was a special gift they have, some kind of a unique blessing. And you are supposed to get only through that special gift.
Lets say you are a kid with the costliest video game in the neighborhood. You got it because your rich Uncle Joe gave it to you. You pride around telling you are the only guy who has it. You also know nobody else can have it because no one near has a rich uncle Joe. An year later you find another guy having the same video game, which he bought after selling lemonade on the footpath.
Now not only does he have the video game, but he has it without the rich uncle joe. In other words your rich Uncle joe isn't a special distinction you have anymore.