system
Given the following post, respond as if you're commenting on Reddit:
human
Why do some nations that produce enough food to provide for their whole population end up importing that same food?

I believe this is the case for Canada with wheat.
gpt
The reasons can be very simple. Canada has free trade with the US. The border between the two countries is very long and most of the population of Canada lives very close to the border. As a result, the transport cost of transporting a good across Canada may be larger than the administrative costs of importing it from over the border in the US.

The price of a good (e.g. wheat) may favour Canada at one place along the border and may favour the US at another place on the border.