It's a distance-from-the-Mediterranean phenomenon
Not only! I lived in several parts of France. In Normandy, they didn't catch yet the concept of 'car', and are unable to drive safely. On Caen's ring road, each time it rains there's a car crash, so there's a car crash every day. . In Lorraine, you can walk and cross the streets of Metz without even looking before, and car drivers are polite and respectful to each others. In Paris, the only rule that matter is "watch the front of your car" and don't care about the rest. In Toulouse or Marseilles, there's no rule at all, everything is possible.