Moral economy, as a set of rules which regulate market transactions, has been the object of much research and debate since the 1980's. Classical sociological authors such as Weber, Simmel, and Toennies also dealt with this subject, however Weber in particular dwelt on the rules of the moral economy in the financial markets. This work sheds light on Weber's contribution, as distinguished from those of Simmel and Toennies, formulating two models of business relations, one oligopolistic and the other based on free competition, and shows the consequences on competitiveness in the World market that flow from the prevalence of the one model or the other. The conduct of actors in financial markets is also accounted for, making reference to Weber's writings on the London and Berlin Stock Exchanges, and to investigations on contemporary financial markets.