Storing and shipping liquid oxygen is not that energy efficient. The point I'm making is that the oxygen can be used at the source of production (splitting water) to produce more fuel. Liquid oxygen storage is not something that one would do in most facilities while almost anyone could split water and utilize the oxygen to gasify their waste streams to produce syngas for heat and electricity production.
Liquid oxygen is trucked and stored all over the place. Most hospitals get their oxygen by warming LOX (you can see the frosted-over serpentine warming systems by the tanks if you look carefully.) It's easy to ship and does not suffer large losses when doing so.
You keep bringing up this point, but the idea isn't to sell the oxygen on this market, but to utilize it at the source to upcycle carbonaceous matter into usable fuel (Hydrogen, methane and carbon monoxide...i.e. syngas) for use alongside the hydrogen gas that is produced via electrolysis.
This is useful in remote locations (cell towers, villages, etc.) where a liquid oxygen tank would not be viable.
Just to clarify, when I say, "not cheap" I'm more or less referring to the energy costs and not the actual monetary costs. It's energy intensive to bring air down below −183 °C to liquify the oxygen out. When contemplating future energy sources, it's these round trip energy expenditures that are most important. Not to mention the infrastructure costs (liquid oxygen tanks, roads that can safely handle shipping, etc. aren't cheap either).
The market value of oxygen tells you how much your own production of oxygen is worth, even if you don't sell it on the market. If you could replace that O2 by buying it, its value to you is no higher than that replacement cost.
