'Argoland' has an awkward monetary system - its currency are green, red and yellow points. Their value is different - red points are almost valueless - only basic items like basic food can be bought for them, green points have a bit higher value and only yellow points have real value. Conversely, only employed are paid any yellow points, the more the higher their class. That means only those with class over 4 (and practically 3 because there is a shortage of jobs for class 4 and no jobs for lower classes) can get any yellow points officially. Therefore, a black exchange market for points flourishes.