"Human beings act in ways that are motivated by economic rationality, and will always seek to maximize profit" *looks upon millions and millions of words of fan fiction* friend your model has something of an explanatory gap
It's sort of like one of those mathematical proofs that goes through a whole bunch of convoluted steps that look reasonable but are subtly flawed, except at the end instead of getting "1 = 2" or the like, you get "humans = money".