I have an honest question and let be honest to each other .
70 percent of international student across the world are hardly to pay off there tuition fee like those ones that went for undergraduate 4years program .. 20hrs a week is only allow for student to work which is insufficient to pay off tuition fee. Still many are still coming with just only one year tuition fee and living expenses . You been there years now and you have witness how things is going but we here don't really know how most people survuve to pay off there tuition fee with out being caught by the Canadina immigration.... because i know 70 percent of international student hardly pay off there tuition fee with 20hrs a week for those ones that didnt have strong sponsorship.
It's not possible to pay tuition fees, rent, food and other living costs on 20 hours per week except you're lucky enough to be making $50 an hour or something. I was blessed enough that my dad was able to pay for my tuition and rent throughout my schooling so it wasn't always an issue. Although I have occasionally worked more than the 20 hours, maybe 24 hours a week and then 16 hours the next week, sometimes things happen that you get scheduled for more hours.
However, I do know people who have worked full time (35-40+ hours), whilst in school which you're not supposed to do other than during a scheduled break (e.g. during the summer). The only risk with this is when you're applying for a PGWP they might reject you because you violated the terms of your study permit as they have a way of checking how many hours you've worked except you were being paid under the table (cash). Again, some people have been able to get away with it, some haven't.
I won't judge or police anyone and tell them you must only work 20 hours or less because I know how hard and costly it is to live here, especially without having strong financial sponsorship backing you. I would only say be careful how you go about it especially if you plan on staying here long term (i.e. getting your pgwp, PR)
I have always thought the 20 hours a week rule is unfair but you have to keep in mind that if you're on a study permit you're here to study and not work. Plus they're assuming you can afford the costs of being here when you applied.