Wrong. Even if it is like this, it's got nothing to do with the code. It's just a decision they made to follow. And the reason for that that I believe is just to make the instances more suited to completely unrelated people stumbling across each other, rather than for whatever features you seem to think of.
Market board, retainers and the like all are no different than armoire or aesthetician. They are separate pieces of the database that work separately from the remaining code and are active only "on demand". The proof is easy. Try to do something unrelated to these things when having those open, like change class or use food. Aesthetician aside, of course. You won't be able to. Why?! Because at the moment, you are connected to a different database. It's like trying to overwrite a file that's open in a different program.
I am talking about supposed limitations of the code, you are talking about the way the code is used. Those are two different things. Don't mix them up. For the code, the inside and outside are no different. An instance is an instance. If they can make a large limited in amount instances that allow gardening or stables, they can make small, unlimited in amount instances with the same characteristics. They can...provided they have the hardware for that. That's all it boils down to.
