So, fuel is a precious commodity, especially if you fight far away from your "home" where there may be many gas mines.
I notice in the game that used to be the Swarm AAR that after going a bit further and making peace, Caslon got the following stats:
My stock: 336,1k
My demand: 11,8k
Galaxy stock: 1037,8k
Galaxy demand: 67,8k
This is by far the most demanded galactic commodity. Shouldn't prices rise? Especially as a part of the fuel problem is having enough of it in the right place.
I also notice the flip side of mercilessly hunting the gas mining bases and resupply ships of your opponents. When you make peace, their freighters comes and makes your mines run out of reserves... The mines that also took a hit during the war.
It really pays to have some resupply ships on good caslon sources, even if quite near or at home. Civilian ships won't refuel there, and they will not pick up goods either. And they can be deployed in addition to another base.
A star base will sell its goods, even if no commercial center, btw. So no way to keep the fuel on those for yourself.