Utilitarians have struggled for decades to properly define "utility". The approach Bentham took (the father of utilitarianism) is completely different from John

Utilitarians have struggled for decades to properly define "utility". The approach Bentham took (the father of utilitarianism) is completely different from John Stewart Mills, also a giant in utilitarianism. "Utility" is a far more vague concept than "efficiency". Maximizing efficiency is less complex than utilitarianism. Capitalism strives for efficient allocation of resources based on supply and demand, i.e., what people have and what people want, it makes no promises on maximizing total happiness or equitable distribution. For a utilitarian "putting a scarce resource to its (most productive) use" would indeed be to provide the maximum amount of enjoyment. But for a capitalist, it's simply the amount that someone is willing and able to pay for it. I know some free market proponents use utilitarian ideas to make their point, and there is overlap, but they are a bad fit. Utilitarianism is a moral theory based on maximizing total good. Capitalism is an economic system that seems to have worked more than most other systems. There are moral arguments for capitalism, but they are based on individual freedom, not collective happiness.