Isn't there just some average value floating around out there to estimate the cost of an ounce-mile of mail? At any rate, your food gets shipped from same plac

Isn't there just some average value floating around out there to estimate the cost of an ounce-mile of mail? At any rate, your food gets shipped from same place and ends up with you. Isn't the co2 going to be basically the same if that's to a grocery store first or to a big cooking joint? Assuming the locations are roughly similar.