The Treasure Kingdom

Pre-Trash Kingdom
The Treasure Kingdom is just a single very elitist city state. They take in trash they deem valuable and greedily hoard for themselves. The citizens strive to be as close to this perfect sparkling unattainable ideal as possible, and those who do not fit their narrow definition of treasure are banished. Their reasoning is that sometimes things are wrongfully thrown out and that they are saving and preserving forgotten treasures. As a result, their culture places a lot of value on art, beauty, and cleanliness.

Post-Game
At the end of the game, the Treasure Kingdom still exists as a separate city-state outside of the Trash Kingdom’s borders, but they’re under new rulership, exactly who might be dependent on the player's choices. The people still value art and enjoy gaudy and sparkly things, but are now a lot more open to trade and diplomacy.