You also have to remember that startup and infrastructure costs were a LOT higher when WebVan and HomeGrocer started (although WebVan did go above and beyond th

You also have to remember that startup and infrastructure costs were a LOT higher when WebVan and HomeGrocer started (although WebVan did go above and beyond the call of duty with their spending on top of that). Amazon already has all of the technical infrastructure they need, so it's just a matter of keeping the storage and transportation costs down (e.g. not spending a billion dollars on a warehouse).