Good thoughts Doc, but I would offer a different perspective.
The terminology is correct, but the goal of the hatchery program may change as the fish respond, or not.
Clearly nobody can harvest fish that are not there. If a river is so critically low in spawning adults (for whatever reason) that the stock cannot be restored in a reasonable amount of time then a 'conservation hatchery program' is considered a potential means to help the stock recover. Is this ideal? No. Is this biologically sound? Maybe, depending on the origin of the hatchery stock. Will it help put spawning adults on the spawning grounds where none exist now? Yes. Will this put eggs-in-the-gravel and marine derived nutrients into the river? Most definitely yes. Will it be successful in developing a self sustaining population of salmon where none exist now? Perhaps, but the jury is still out.
In almost all cases, conservation hatchery programs do not mark the juveniles. They are indistingushable from wild fish. That eliminates harvest by recreational anglers, but not Tribal or commercial folks. The idea is that by not marking the fish, more will show up on the spawning grounds. However, that greatly exaggerates the success of recreational anglers. In reality, the folks on this BB (like me) are not effiecent enough to make a dent in most salmon populations. Can't say that about the other users however.....
However, once a conservation hatchery program successfully establishes an appropriate number of spawning adults, the program should change. The juveniles should be marked, and the contribution of the hatchery and the habitat should be estimated. This last step is very important. At some point in the process, fish managers MUST know how many of the returning adults are coming from the hatchery and how many are being produced in the watershed. Too often, this step is not taken. Perhaps because some folks don't want to know. As long as the adults are showing up in harvestable numbers, they're happy.
But that's where your observations are correct. At some point, if the conservation hatchery program is successful, it needs to change to a harvest program. The hatchery juveniles must be marked, hatchery adults should be kept seperate from the wild fish, and the habitat needs to be restored or protected to maintain whatever level of production is occuring in the watershed. And yes, all hatchery fish that are not needed for the adult broodstock should be harvested, kept seperate from the wild fish, and used for marine derived nutrients throughout the wateshed.