Yeah I don’t think it’s especially common. Maybe out west or in the prairies? I don’t know many people from there. In the marritimes it’s all “aboat” as far as I can tell, and Ontario I think says it like American “Abowt”.
Part 3 of the north american accent tour, by Erik Singer, on the Wired YouTube channel, does a great job breaking down different Canadian (and north american) accents.