If there was the demand in a specific area, then the free market could provide a solution. A player with an alt account and a penchant for mining could park a carrier next to a tritium hotspot and mine tritium for resale (at a handsome profit). The carrier could also stock mining gear so that others, whether passing or not, could mine and sell to the carrier.
You can't buy and sell to the same carrier market, so this would really need two alts - one running the sell carrier for other miners, one running the buy carrier for passing explorers, and then they manually transfer cargo between the two when online as needed.
The problem is that mining is never a workable free market solution to this, because there are other more efficient ways to get Tritium out there.
Let's say a top miner can mine 200t of Tritium per hour and has mapped out a series of hotspots to make this reliable. To earn 100M/hour [1], they need to charge 500,000 credits per tonne for the Tritium. To provide 10,000 tonnes of fuel to a passing carrier, they need to work for 50 hours.
A disposable tanker carrier, on the other hand, costs 500 million net for the carrier (purchase cost minus scrappage payment), plus 50k/tonne for the fuel. At the same 500,000 credits per tonne purchase price, it would be capable to operate on a 100M/hour basis at well over 50,000 LY from the bubble, but would only take about 45 hours to do that and can deliver to the carrier that needs the fuel rather than them needing to find the mining installation.
The tankers are cheaper, faster
and more convenient than the miners in almost all circumstances under the free market, as well as requiring far less skill and practice to provide (mostly it's semi-AFK jumping or short-turn hauling); someone more altruistic running their fuel service on a break-even basis (or the explorer's own alt) could deliver Tritium to the far side of the galaxy for just 200k/tonne.
To make mining viable (on a free market basis, I'm sure there are people who'll do it purely for fun and altruism) would require some sort of highly unpopular change, e.g.:
- earning rates for all NPC activities to be reduced to 20M/hour maximum - at that point, mining would outdo tanker carriers in a substantial proportion of the galaxy, because the majority of the tanker's costs are fixed, but a carrier owner can pay well above 20M/hour to attract miners.
- Tritium efficiency to be put back to the original levels of ~1T/LY. At that point even a disposable tanker carrier can't get out more than 25000LY and can't carry any useful amount of fuel that far; setting up the supply caches necessary for it to get out a little bit at a time would push the costs up to ridiculous levels
- Tritium is made mining-only, even in the bubble.
So it's not happening, I think.
[1] A top miner can earn a lot more than that in the bubble, of course, or out in the black could earn comparably from exobiology. So free market, probably needs to pay a lot more ... which makes the disposable tankers
more effective as their fixed costs don't change but the pay goes up.