The prize machine kept selling extra carry slots after they stopped doing anything. Mass placement starts with ten slots and caps at twenty, so the tenth perk already reaches the ceiling — every one after it was a prize that changed nothing. The machine now stops there and moves on to the rest.
A finished product group paid its coin every time it was completed instead of the first time. Taking one copy out of a completed display and shelving it again paid again, over and over, and it drained the store's coin budget away from the groups still unfinished. A group now pays once.