ChanteyLass, they're not mostly used now by young people but they were 40/50 years ago and earlier. Why French-Canadians use them, I don't know. Kids here say "mamie" which doesn't sound like "maman" while there's not much difference between "mamie" and "mommy" in an English/French speaking country. Besides I don't think that French-Canadians have the same feeling of "young, modern, avant-garde" for American English words as we can feel here. I really don't know what other French-speaking people use (GF-GM endearment terms but no words from outside mainland-France )