That's because France like many other countries, but not Canada, signed an international treaty that standardizes road signs: https://en.wikipedia.org/wiki/Vienna_Convention_on_Road_Sign... That makes it a bit easier to drive safely across countries without reading all local languages.

Edit: Huh, apparently "stop" or the equivalent in the local language are allowed by the treaty. Didn't know that. https://en.wikipedia.org/wiki/Stop_sign