I've played a new save to have a look at the lumberjack quest and the church shop, which I have missed before.
The lumberjack quest unlocks a new buff potion, and it seems that this potion can also be sold for money. 5 gold each.
I think this potion itself has some limited use, as an early game replacement of rift potion (for escaping) and time freeze potion (for other actions).
This potion accelerates player action, which is useful for dangerous situations. However it costs HP, so it can also cause problems. I think in early game this can be used to solve some farm dungeons that are otherwise difficult. It won't have much use in late game.
Selling this for money is only viable in mid-game, when you have a steady supply of blood from the scarlet flask, and you still go to tier 1 forest for mandrake.
In early game I don't have much spare sanguine essence for this. In late game I don't often go to tier 1 zones, and tier 2 zones don't provide enough something fey for crafting this. There is also no need for so much money in late game either.
About the church shop, it sells ingredients for something holy, but I don't need much of it either. It is indeed an early-mid game shop, just like the dev log said.