The website seems to provide absolutely no capacity to pose questions that are not readily evident in its FAQs area. I am unable to find a way to have CTV and CBC Gem installed on my ROKU and the website will not let me pose the question as to how to do so or if not any they do not provide access to CTV or CBC Gem for Canadians when they do so for Global and some other Canadian sites. Am certainly going to turn my unit if this is an indication of ROKU's customer service approach.
Without commenting on Roku's customer service (or lack of same), they wouldn't answer that question anyway. It's up to the providers to create a channel. Roku doesn't really "provide access" or restrict access to anything. You would be better off asking CTV and CBC Gem why they don't have Roku channels.