it's not just the money.. how many slots do the cities have? avengmil, a 10k townsland has 13 slots. used 9 slots already (2 granaries, 2 banners, 1 scout, 1 healer, 1 smith, 1 market, 1 demo). then again... avengmil doesn't need to buy all that much food, so it's somewhat moot.