Supply and demand, and inflation system would be pretty neat for every game.
You couldn't mass harvest or produce a single item and then dump them to the vendor for huge profit as the value would go down more there are that item in the world.
Town would become rich if you spent lots of gold there and prices would go up. More beggars would appear on the streets, place could turn into a trading hub..
But you can't expect any of that from modern incompetent game devs.