That's true! When hubby was in the Military, he went overseas on some UN deployments. On leave, they would often go to Germany for R&R and do some traveling - sometimes to France. One of his buddies was a Frenchman from Quebec who decided he'd be the "interpreter" for his friends while in France. It turns out apparently NO ONE could understand his French! The guys got a real laugh from that and the Frenchman was furious - likely because he was embarrassed.
We have experienced the same in Canada in that we went to a football game in Montreal with another couple; "Lucy" was French but from B.C. The football game was between Montreal and the B.C. Lions. We lived in Petawawa, Ontario and drove up to Montreal the day before the football game so we had booked hotel rooms. Lucy decided she'd "check us in" at the hotel desk because, after all, she spoke French and she thought she'd be able to move things along. You need to know that Lucy was 5' nothing, a little bit of a woman - very petite. She started speaking to the desk clerk who simply stared at her with a puzzled look on his face. Lucy continued to speak to the guy and still, nothing. When we asked what was wrong, she said that the clerk was pretending not to understand a word that she said. She was furious!! She was hopping up & down - it was actually quite funny in retrospect. We eventually got our rooms - using English.
It turns out that in Montreal, (or perhaps Quebec?) if you don't have the correct "accent" they'll pretend not to understand anyone who is at least trying to speak the language. I experienced it at the football stadium when asking where the restrooms were - that I knew in French - and was totally ignored. The stadium was huge so to wonder around looking for the sign that said bathrooms was quite the feat.
So for the French whether in Quebec or France, they'll ignore you if you don't speak the "right" French apparently. Hopefully, things are better now.