For newer members who may not realize what was going on during this performance;
The occasion for this performance was the 100th running of the Tour de France and several artists performed here over the course of the day. The location was Hotel de Ville (city hall).
There was some sector of the entertainment industry that was on strike and they were protesting at this event (what I don't know). You can see them holding up pamphlets and hear them booing. I'm sure Alizée knew little or nothing about what was going on.