As a French, it was strange to see Happy Meals called Joyeux festin in Montreal, and other stuff like that.
In France, we also got a law (Loi Toubon) saying you must translate anything from another language to French, for exemple in ads (most propably for preventing misunderstanding).
But you can still have slogan in english (or another language).
Looking at the impact of the City of London on Greater London, or the finacial services sector on Dublin or Silicon Valley on Palo Alto it seems to me that the flight of major, centralized economic powers (with the ability to distort democracy) is a net win for most locations.
Quebec continues to do well despite the relocation of a few businesses.
Not everyone who left QC is a francophobic, and while I do understand some of the French side's worries, things like Loi 101 are sometimes "too much" (like requiring board games to be in French)