We don't have general system in place that would somehow prevent this. The world runs on capitalism and everyone needs food and roof. Whoever has the power to give them or take them, has the total power, and can play with the system more they have wealth. Social democracy is some sort of middle-ground but it is not enough, because it is not applied everywhere equally, and it is hard to define what is selfish and non-selfish.
Laissez-faire capitalism is not synonymous with all forms of capitalism. We could and have in the past curbed runaway wealth and power. Pretending nothing can be done is, at best, ignoring history.
