Mooncake Festival

Every year, at this time, I would think to myself incredulously why a simple task of buying a couple of boxes of mooncakes would turn out to be an all out war. Darling and I do not have the habit of pre-ordering mooncakes way before the mid-Autumn festival (like one and a half months before). And every year, we would go through the same old horrifying shock. And tada... this year was no different. When we happily went down to the mooncake stalls at the shopping centre near our workplace yesterday to buy mooncakes for our families, we were stunned to find every single item on the stall-of-our-choice's catalogue pasted with the big red 'SOLD OUT' sticker.
Me: Erm.. so if everything's sold out why are they still here?
Dear: They've already paid for the rent, so why not?
-_-

Dear approached the person at the stall and had an interesting conversation that I can't help buy pen it down.

Staff: Actually we have delivery twice everyday.
Dear: So can we pay and leave the mooncakes here and collect them from you after work?
Staff: Sorry, no you can't.
Dear: What time is the delivery?
Staff: 11am. You can come back tomorrow. 12pm is a safe time. We've got a delivery now. The driver's on the way.
Dear: So can we pay for the mooncakes and come back later?
Staff: Sorry, no.
Dear: So I have to queue here.
Staff: Yes.

And so we queued and managed to get our mooncakes eventually. But while paying, we overheard this.

Stall to staff: From tomorrow onwards, ____ mooncakes will not be available anymore. And for today, we have only 20 boxes left.

Why like that??? They are only mooncakes.......... T.T