This really deserves a journal entry on its own but...
10,000 years ago, humans were mostly hunter/gatherers.
Agriculture changed that. With surplus food came larger populations which could support specialists. Specialists were people who could defend the village from barbarians, the priest who could help the city get along with "the gods", the people who made pottery, jewelry, metal works, as well as the people who could sell them.
Currency allowed people to trade more easily as well as provided a way for the village elders to "tax" the people.
In Elemental, the only resource available to me that doesn't "store" is food. That's why I made merchants use food because I could have it reserve one of your food resources.
In v1.09, we will have specialists instead. So a merchant will use up a specialist slot. The number of specialist slots a Kingdom/Empire gets is the total population /10 (the idea is that 10% of the population are specialists of various kinds though historically it's a bit less than that but this is a game not a historical simulator <g>).
So your village with 80 people will provide your Kingdom with 8 specialist slots. A merchant would use 1 slot. A Study would use another slot. You could build multiple such buildings as long as you have available specialist slots available. Similarly, a military unit would use a slot (not 1 per soldier but rather 1 per unit giving the advantage to those kingdoms that can field larger groups AND get us back towards a more epic feel because if a unit costs a specialist slot, the base training time of training ONE unit can be lowered and thus allow training of much larger groups to be much quicker getting players back to fielding much larger armies).
This is hardly an original idea of course. Sins of a Solar Empire has a supply level, GalCiv II has logistics (and incidentally, we do plan to introduce more logistics into Elemental to deal with singular super armies).
To the argument "You shouldn't limit the # of workshops by population" I say this: In the real world, and this is a pretty well known fact, that only a tiny % of people are capable of being a specialist. It's actually less than 10%. Most of us aren't specialists. If it were easy to start up a workshop or run a market or be in charge of a university then what's stopping people from going out and doing that? The answer is that most of us can't do it, only a small % of the population is capable of doing it.
Most of us in the real world are drones.
Now, if you'll excuse me, I am going to go stare at the wall for a bit while drooling. 