The hypothesis of the Americanization of European club sports competitions has been the subject of much analysis. The main concept examined in this article is the growing reliance on demographic criteria, particularly the economic potential of the market zone. The purpose is to consider the consequences (rather than the likelihood) of a scenario in which demographic criteria become the sole variables of club location and their qualification in European championships. Such a change would have consequences for the both the private (shareholders or potential investors, direct supporters or general audience, sponsors, etc.) and public (federations, local government, states, European governing bodies) sectors. The first part of the paper reviews the relevant demographic criteria in sports and then recalls the current strategies for league organization on both sides of the Atlantic. The second part is devoted to assessing the consequences of these strategies for those involved. General questions are then raised about the future of professional sports teams in Europe. The analytical method is based on principles taken from demographics, geomarketing (as geographic information system, GIS) and the political economy of sport. The data concern six major leagues on both sides of the Atlantic.