I think it'd mostly be exploration ships. Water ice may not necessarily be easily accessible for ship in a new system, so parking the ship in an area with abundant sunlight and just recycling their fuel while they take readings and so on would be a pretty ideal choice and it gives the crew peace of mind - while water ice is common in the universe, crews may have (unreasonable?) fears of jumping to that one system that has none and being stranded.
Scout ships might also get quite a bit of use out of such a system. "Picket" ships were common during the Kafer War, arriving in an undeveloped system, finding some place to hide (like in a ring system or possibly on a moon) and just watching who passes through for weeks or until something of interest passes through at which point they'd speed off to report. Such a ship wants to find a good hiding spot and sit there, which is reasonably ideal for recycling water back into fuel.
I doubt Mechant ships would use such a system. Unlike Traveller, ships like the Mammoth in 2300 show plainly that 2300 uses containerized freight. Time is money, you don't want to sit there with a fully loaded ship that is just waiting for fuel to finish cracking; the cost of buying pre-cracked fuel is likely a non-expense compared to the time you save just being able to speed off the moment your ship is loaded with freight.
As for scouts or military pickets, I guess they mostly use other kind of power plants not needing such refuelling (moslty fission ones, as fusion ones are too large).
Scouts need to have long endurance, and even those closed systems would have some loss, andas minimal as it might be, it mounts with each stop. Military pickets must be ready to flee at short notice, andhaving to process the fuel will take quite longer than the stutterwarp discharge (that is the minimum time stopped).
As for merchant ships, most are dependand on local interface and Orbital Facilities, and those can supply the fuel as much as load/unload cargo and passengers.
but with no FTL Coms you have to call up for ships to collect your cargo, given the cost of fuel you will want to have your next cargo to be loaded, wait for them to boost, Load then brake orbit.
unless you are on a fixed seclude and your company can afford to tie up Cargo Lifters waiting for you you will have to wait, even then what if your off seclude? it costs more to run Interface Craft than Interstellar Ships.
In most cases, the cargo waiting to be exported will be lifted to orbital facilites to wait for ships to take it, and cargo arriving at system will be unloaded there too, waiting to be downlifted to the surface as interface services allow for it.
In less developed areas, most ships will have their own interface systems, be by being able to land, or something like my own
Steer Wheel Warp Frame and Barges designed system (in this case for MgT2300AD, not sure if it could be done with Star Cruiser).
