Having to pay for things with a thousand of something kind of makes the logic of the world break down if you look at it too closely. Like, no one is counting those, you would need scales that are big enough to fit thousands of coins to weigh them + a huge set of counterweights, and this is in a world where things like Lighten Object exist. There is no way to make commerce make sense in a way that isn't very inconvenient to the players.