Olympic cosmopolites

A friend pointed out that it is not uncommon for athletes to change citizenship in order to compete in the Olympics. The practice is also common in international soccer, basketball, and other sports. While I doubt that these actions were taken for cosmopolitan reasons, isn't the effect the same, nonetheless? 

Sport is interesting when looked at through the lens of cosmopolitanism. Counted positively are both the Olympic virtue of the world's athletes peacefully coming together in a celebration of excellence, and  the participation of athletes of one nation playing for teams in the national league of another nation (the Argentines Messi and Ginobli loved by their respective Barcelona an San Antonio fans, for example). Counted negatively are the riots and violence between fans of different international competitors, most notably in soccer (though these negative passions arise within nations between rival clubs as well.)

I don't think it matters why athletes move around the world to compete in sports for different club teams and even nations. I think the fact that they do helps the cause of cosmopolitanism.