The process of making durian ice mooncakes. [Photo/VCG]

"New houses will be built every month, but those 6,000 boxes of mooncakes are all Shanghai can have this year," said Qian Guomin, who claimed to have been a mooncake scalper for two decades.

Chen, the secretary-general of the confectionery association, estimated that the city will sell 21,000 metric tons of mooncakes this year, up 0.5 percent from last year.

"The situation is far better than we expected. With multiple adverse conditions, we thought there might be a drop from last year," said Chen.