I guess that's a legit point. I buy it to a certain degree, but the counterexample would be that I didn't hear too many people complaining about the Spurs back when they were winning championships. They had a French point guard, an Argentine shooting guard, a Virgin Islander power forward, and then the rest of their rotating cast was a crap shoot (most probably American, although Nazr Mohammed is Ghanaian).
But you're right - you'd hear a lot of complaints if it came to that. "I" wouldn't care - I want Carlos Santana, Shin-Soo Choo, Carlos Carrasco, Asdrubal Cabrera, and whoever else to win win win. I don't personally care where they come from.