Detail price list

When I go to eat my favourite Wantan Mee. I saw this in the price list.

believe it or not, complete price list up to quantity of 12 orders
I asked the Wantan Mee uncle:” Why need to show the quantity price?”
Uncle replied: “Easy for me to refer pricing, my mathematics was no good….”
I asked again: “why no quantity discounts? Like eat 10 free 1?”
Uncle replied: “I don’t think there will be 10 people come in one shot, no need to put this kind of discount.”
You see….How this Wantan Mee Uncle make money? If he forsee there is no up to 10 customers come in one shot, why he want to the price list up to 12?