The two largest buffet chains in Ontario are Mandarin and Imperial Buffet (both serving Chinese-Canadian cuisine). There used to be Buffet King (Chinese-Canadian) as well.
Many of my older relatives (they're Chinese) complain about how the food in those buffets aren't authentic.
Obviously they aren't authentic. They're Westernized to allow for mainstream popularity (and I prefer them Westernized).
Canada's Wonderland has the Marketplace International Buffet, which primarily serves Western food, despite its name.