That only works if you assume that "rational" means "make as much as money as possible in the shortest possible time while ignoring any externalities."
Labelling that kind of behaviour as rational is a neat rhetorical trick. But by any objective standard of ethics - or even realistic expectations of medium-to-long-term survivability - it doesn't meet any of the standards required for rational action, any more than any other hoarding behaviour does.
And there's the post-financial view that the real benchmark for rationality isn't competitive acquisition but maximisation of personal and collective opportunity - which is something that markets consistently fail at. (Although again the stock rhetoric claims otherwise - typically with selective interpretation of the available evidence.)
Labelling that kind of behaviour as rational is a neat rhetorical trick. But by any objective standard of ethics - or even realistic expectations of medium-to-long-term survivability - it doesn't meet any of the standards required for rational action, any more than any other hoarding behaviour does.
And there's the post-financial view that the real benchmark for rationality isn't competitive acquisition but maximisation of personal and collective opportunity - which is something that markets consistently fail at. (Although again the stock rhetoric claims otherwise - typically with selective interpretation of the available evidence.)