Why do you think they’re able to make that much money? Not by using their position as the store where the majority of people buys games from?
There’s no good guys when profits are the goal. They might provide good service, the only reason they’re doing so is because they see potential profit.
There’s a major difference between making more than average and being a billionaire. You know what’s the difference between making 500k a year and making a billion a year? About a billion.