I can only really speak to the Australian aspect of how Canada compares, but I can say that in Australia, for domestic Ph.D. students, there are no tuition fees. There is no question of whether there will be an extra cost imposed on students. For international students, there are fees, but for the majority of students who are studying or completing their Ph.D.s in Australia, my understanding is that they would apply for and usually get an international fee remission scholarship.
The fees are there on paper, but the majority of students who are successful in winning a scholarship would probably also get their fees waived or funded by a scholarship, so they wouldn't need to pay anything there. In terms of Canada charging fees for post-graduate research, it seems to be a little out of step with what we would get in Australia.