The oil goes on the world market.
And do you believe we are not paying market prices in the US?
Transportation cost money. Why spend dollars to receive market prices available in the US? And the US Gulf Coast has significant refinery capacity already optimized for heavy crude, but now we get a lot of it from Venezuela.
Unless Venezuela intends to cut a below market rate for the US that Canada would not, while paying more to ship, we will be refining essentially all of that oil.