On the subject of sustainability, I'd always heard the story of eating local, presumably to avoid the environmental impact of transporting food over long distances.

It seems that that's insignificant compared to the type of food we eat:

https://ourworldindata.org/environmental-impacts-of-food#whe...

> Shipping one kilogram of avocados from Mexico to the United Kingdom would generate 0.21kg CO2eq in transport emissions. This is only around 8% of avocados’ total footprint. Even when shipped at great distances, its emissions are much less than locally-produced animal products.