I would guess your footprint is more increased by getting all kinds of stuff (you don't really need). And the stuff being shipped across half the globe.
That's a fair point and I'll admit I hadn't considered that.
Conceivably, we could make electric (or something) transportation systems that can travel across the world and not produce and CO2, but we certainly haven't gotten there yet.
Marine transport is incredibly efficient. Total marine transport accounts for ~2% of global CO2 emission. It would be nice to have, but definitely a low priority.
