There is an allusion to this:

In those days, the police in Hong Kong would ask the food stalls for advice when they went out to have a supper. The owner of the food stall would shout out "bad luck" when he saw the police, because they ate As a rule, no money will be given. So one time, when a policeman went to a food stall and ordered a bowl of roasted goose and pork noodle, the boss deliberately said: "This gentleman is so knowledgeable about eating, I wonder if you want the left thigh or the right?" The policeman asked. He was stunned, "Is there a difference between the left and right thighs?" he asked. "Yes. Of course there is! The left thigh is much longer than the right thigh." (In Cantonese, it means that the left leg is much more delicious than the right leg.) So, from then on, it was spread that when eating roasted goose legs, the left leg tastes better than the right leg. . Although today's police officers no longer know how to eat Bawang rice, the mystery of the left leg still dominates barbecue restaurants. Regardless of whether they are selling ducks or geese, the left foot must be sold first.

Some people also say that when geese sleep, they stand on one leg and use their left foot. So the left leg is more resilient and the right leg is softer.