I'm not so naive as to believe that everyone who goes to the Olympics does so simply to compete the best they can for their country, even if I think that should be the major driving force. However, I do believe that one aspect of the Olympics is that you are representing your country. I remember, about 16 years ago, hearing about some American guy who decided he wanted to compete for the Suriname team, even though he could produce no evidence that any member of his family had ever hailed from Suriname. I remember thinking there was something just wrong about that. As happens so often in time, history repeats. In the most recent situation, WNBA player Becky Hammon, spurned from her U.S. team (she's a U.S. resident and citizen), has chosen to play for the Russian team. I know that the Olympics formally lifted the ban on professional athletes back in 1992, but isn't it a little soon to allow Olympic free agency? As an Olympian, you are a representative of your nation; for two weeks, you are that nation. From a purist standpoint, representing a nation that is not yours simply because you wanted to go to the Olympics and were deemed not strong enough a component for your country's team runs contrary to the spirit of patriotism that should, at the very least, be a part of each Olympian.
For what it's worth, because I've heard others claim that nobody complained when Hakeem Olajuwon played for the Dream Team - he didn't do so until after he became a United States citizen. In other words, he represented his country. Apples and oranges, people. He did the right things to get on the team. He wasn't motivated primarily by selfish ambitions.