As a matter of fact, there are situations where students and companies enter into agreements where they both benefit, and there is no (or little) remuneration. The student gets a reference, with relevant experience and the employer gets the talent and the outcomes. It's often unconventional, with the student coming to work when they're available (often they may be working unrelated roles so that they can afford to pursue the unpaid role).
The University of Waterloo (thank you, Rocco) is examining their policies and approaches to unpaid positions and trying diligently to respect the CAFCE guidelines. They're bringing creativity to how to identify "remuneration", the CAFCE term, such that honoraria, stipends, equity positions, hardware (tools and devices) provision, etc. would be recognized. It's relatively critical to ask the employer what they would have done (would the work have gone undone?) if there was not a student available in the so-called unpaid role.
Questions about insurance for the student and the Ontario Tax Credit (whether or not the amount is enough or if awareness is sufficient) were brought forward and it seems we may not have wide understanding and clarity on where we're at on these points).