Why is there tension between Kino and his people and the people who live in town? For example, why does the doctor look down upon Kino and his people?

In "The Pearl" Kino and his people are put down in so many ways. Since he and the rest of the villagers are uneducated the townspeople feel that they can take advantage of them. Which is what the pearl buyers tried to do to Kino when he tried to sell the pearl. Plus, since they don't have any money, doctors and nurses refuse to treat the sick ones because the villagers cannot pay them and the doctors and nurses just don't like going to their village. They are looked down upon so badly that the doctor considers them animals and not human because of their race. It is an example of colonialism and the exploitation of indigenous peoples.