Political systems depend on power exercised by people to enforce law. When the real power transfers to the wealthy, which in peacetime happens as surely as large masses draw objects into orbit through gravity, they will use that power to draw in even more power and wealth. The only protection is politicians, and other democratic counterbalances like the justice system and the media, acting in good faith. History has shown repeatedly that that cannot be depended on. All it takes is for one generation's politicians to defect for personal gain and the avalanche of corruption starts. Wealth is power, capitalism amasses wealth, and wealth will blindly hoard itself to death. If one wealthy entity abstains, other wealthy entities will grab that power instead, because that power will insulate them from any consequences of doing so. Believing that politicians will ever extricate themselves from the influence of wealth and power by their own volition is ridiculously utopic.

Life being a zero sum game is not a fundamental part of Marxism.