I think it is an American/European thing but only in a positive way. Italians get behind Italian riders just like Americans get behind American riders (Landis was applauded all along the route in the Tour of Cali). But there are just WAY more European cycling fans so it seems (to an American cycling fan) as if its unfair to American racers who are returning.
I kind of disagree with you about people labeling Basso as a "hero", he certainly was treated that way before the allegations but despite the ad you cite, the response to him is much less now. He's an elite athlete who was suspended for cheating and after paying his dues he's back plying his trade. No more mentions of him conquering the cycling world. Everyone makes mistakes and everyone is entitled to a second chance.
In the US most sports fans don't want to know about doping athletes, if they did you'd hear a lot more about football players and GOLFERS using steroids. The sports media is all upset about it but the fans, not so much.