You don't need the GRE in the sense that not having it will not break your application. I'm not sure if it's because of marks and/or letters of recommendations, but I got accepted to UofT in the first round of offers without writing the GRE. For what it's worth, I also got accepted to Queen's without the GRE.
Caveat: This is one person's experience and there are a ton of mitigating factors that might make the GRE more important for a given individual. It just isn't by any means essential or even needed if you have a strong application from a Canadian, second-tier university.