They do not serve, they earn money. And to earn money you cannot rely on American tourists only (I am aware this is hard to believe). They have a rather strong presence in countries with a diversified hotel market like Germany, where you find IHG, Hilton, Accor and others all on equal terms. They keep away from areas outside the main capital areas in oligopoly or monopoly markets like France (Accor), the UK (Hilton, IHG), Spain (NH, Accor).