Wealth is correlated with greed, dishonesty and cheating -- are these effects or a causes?

There's a wealth of psychological research that correlates wealthy people in the real world with negative traits like rudeness (people driving fancier cars are less considerate of pedestrians and their likelihood of cutting off another driver is correlated to the cost of the driver's car); greed (rich people take more candies out of dishes set aside for kids than poor people); generalized unethical behavior; cheating at games of chance; and overall stinginess.

One possible explanation for all this is that getting rich is easier if you're dishonest, lack empathy, and cheat whenever you think you can get away with it.

But consider that in a rigged Monopoly game, players who won due to an obviously unfair advantage (being given twice as much starting money and twice as many dice-rolls) acted like dicks throughout the whole game, and then boasted about their "brilliant tactics, their finesse at the game of monopoly and their daring moves."

So maybe the causation goes the other way: maybe getting rich is mostly a matter of dumb luck, which we justify for ourselves by convincing ourselves of our superiority, which leads to us treating others as inferiors.

But why are they more likely to cheat, lie and to cut off pedestrians? And why are they less likely to give to charity?

It may be in part because they are cut off from the reality of poverty living in an upper-class bubble. But primarily the researchers found that greed is actually viewed more favourably in upper-class communities.