"One cup of Japanese food, two cups to quench your thirst and three cups to drink donkey meat." What is the allusion of this sentence? How to explain it?

This is the ancient explanation of the way of drinking tea. Taste is sipping, tasting, not cooling off. Generally, it is the way that educated people drink tea. Quenching thirst is as meaningless as drinking water when thirsty. Generally, it is the way that ordinary people drink tea. Drinking a donkey is drinking water like a donkey. It is a way for rude and reckless people to drink tea. Describe not knowing the charm of tea.