There are two meanings of hairy crab in Cantonese

One is the really delicious Yangcheng Lake hairy crab

The other explanation is to describe the stock market after buying stocks. When the stock price falls, the stock loses money, but it is still held but not sold. The money is put in the stock and cannot be moved. The stock holder is called a hairy crab

The term hairy crab is originated from Hong Kong.