The challenge a lot of people face, particularly in the downtown of cities, is that Bell, Telus and Rogers are locking up entire condo buildings with "exclusive provider" access by wiring the building at construction..
So if you move in, you have to sign up with whoever signed that deal. And it's not like you get a discount or some kind of special service, you just lose the choice.
I found this out the hard way when I moved into my current place last fall. I was with Teksavvy (a relatively good 3rd party independent ISP) and when I called to schedule my move, they told me they couldn't service me in my new building, and I was forced to sign up with Rogers (who provide good service, but it's more expensive).
Now I know this is a thing (and I found out it's quite common), so I'll be more careful next time, but I bet a lot of people don't know (or care), so this is yet another way that the big telcos are doing everything they can to undermine customer choice in Canada.