Listen, you are right. These students try to cover their cost by working part time.....which is as per plan of the Government of Canada.
The expectation on paper is correct, you should have enough money to support yourself, but even the every day Canadians know what the true cost of living in this country is and what the motive behind bringing so many TFWs to Canada really is. You know it too, all this is by design.
The financial and economic value of working part time is greater than just bringing enough money to not work during the course of your study. This is my opinion.
And PR was a major incentive for people to want to come to Canada as students too. It isn't anymore. Like
@iSaidGoodDay says, the PR prospect is the last thing that kept them going, take that away and not many will come here. I believe this is what happened in Australia around 2018 or so.
Now some of my acquaintances who know they won't be able to get a PR in Canada or anywhere else for that matter, go to the US. Their plan is to make as much money as possible before getting kicked out.