These zones have multiple purposes, and it's fairly easy to select the desired one and place it on the ground. Hence, the goal of the mod is to make the settlements feel more like the towns from Sim City, which means that you can create special zones and watch the NPCs erect buildings as they see fit.
Fallout 4 Sim Settlements Mod allows you to make Fallout 4 a bit more realistic when it comes to how the settlements are handled by making it possible for NPCs to live independent lives and build things without your input.