Refined is only really necessary for Jump travel. In most systems, chances are there is a lot more in-system traffic. Probably a lot of reaction drives used in lower tech areas as well.Honestly, I don't even know what the reasoning is for selling unrefined fuel. Who has the infrastructure to ship liquid hydrogen to the starport without having the ability to refine it? And what is the business model there? No sensible person is going to actually jump with unrefined fuel in the engines as a normal behavior. So either most ships have on board refineries, in which case the refined fuel market is pretty crap, or they don't. In which case the unrefined fuel market is pointless because the only customers would be folks set up to skim their own fuel who can't be bothered at the moment.