Earlier quoted context omitted.
It actually does not. Shipping food emits very very little CO2 compared to growing it. So the most optimum thing (in terms of CO2) is to plant food where it grows best and then ship it. As an extreme example compare a greenhouse with regular outdoor planting. Or compare growing food where you need a lot of pesticides or fertilizer vs where you do not.
Neither of those examples support your assertion.
The reason is simply that shipping uses very very little energy, it's the rest of the production that uses a massive amount of energy.