Why not just in orbit? Can take products back to earth on returning rockets pretty much for free, or drop them in disposable vehicles if there is more traffic going down than up.
People might ask why do that at all. There are lots of metals in space in concentrated form, solar energy is uninterrupted, and if a large part of your market is off earth it starts to make lots of sense.
Not anytime soon mind you, but one could imagine a future like that pretty easily.
Robert Heinlein’s The Moon Is A Harsh Mistress explored this concept of the low cost of transporting packages from the lunar surface to earth. Now mind you the “packages” were moon rocks shot by catapult at the Earth in a war of independence, but still a really interesting plot point. Everyone should read this book!
Well, it starts at "Not actually as bad as I thought", especially when using ISRU; to actually very cheap indeed if you build local infrastructure. (eg. linear accelerator direct to earth's surface is an actual realistic option).
[Assuming people invest in infrastructure], In the mid- to long-term you might be able to ship goods to earth from a moon based factory cheaper than you could from some earth-based locations.
This isn't really anything special about the moon either, mind you. It's the facts that:
* In comparison, Earth has extremely strong gravity;
To get to the moon from earth, you need the whole thing. To get back, you just need the top half of the lunar module (to get to lunar orbit) the service module (to get to reentry) and the Command module (to survive the reentry). A tiny part of the entire assembly!
(purists might point out that the system could be rather smaller if there was no intention of a return mission... which is fair enough. It's just to get an initial intuition across here!)
People might ask why do that at all. There are lots of metals in space in concentrated form, solar energy is uninterrupted, and if a large part of your market is off earth it starts to make lots of sense.
Not anytime soon mind you, but one could imagine a future like that pretty easily.