To a close approximation the prices of things are proportional to the "soundness" of the scheme. If Digi-Key can afford to put $20 worth of stuff in a box and send it to me overnight, that's their business, not mine. Someone is putting the fuel into FedEx planes full of Digi-Key boxes and somehow that cost is being amortized over all the boxes in a way that is acceptable to all parties.
Sure, but my point is that EVERYTHING you buy has to end up at your house somehow. If you buy it from a store, it has to be shipped to the store, and then picked up by you. If you you buy it online, it is shipped to a distribution center, and then delivered to you. No matter what, we have to get the item to the person who is buying it.
I am just wondering what the actual carbon footprints of the different methods are.