France is one of the most peculiar places that you will ever visit. The French can be pretty fickle when it comes to tourists. Most will not even greet you unless you say "Bonjour!"
Learning the language or attempting to use it is an absolute must while staying in this country. It will get you points with the locals, and it will show that you are at least trying to aknowledge their language. Plus, it will help you integrate into society a lot easier than someone who refuses to learn.