Because Europe and South America don't send their football stars to the Olympics makes it a stupid tournament that means nothing. Its the same thing with baseball, the Olympics isn't bigger than the MLB. Why should they delay/alter their plans on a top prospect by letting him go and play in a minor competition against worse competition?
If Athens was a big tournament and the Canadian baseball team was good/mattered, then it probably would have been different.
Also, was Hero joking about the altitude comment? I wasn't sure the point there
