This just serves to show how truly "progressive" Europeans are as many claim. They are no more "progressive" than any number of rednecks here in Georgia where I live.
If a fan were to impede or perhaps slug Armstrong like what happened to Eddy Merckx then it would seem appropriate for a riot to ensue engulfing the crowds in such utter chaos as to stop the race in its tracks. A kind of Rodney King riot there in France.