How are we made to realize how little concern for the natives the Spanish Mexican inhabitants of the town have?

Steinbeck illustrates how the native Mexicans are marginalized and discriminated against by the colonial Spaniards, who live a short distance inland from the native village on the beach. After Coyotito is bitten by a poisonous scorpion, Kino and Juana travel into town to visit a doctor. Before Kino knocks on the doctor's door, Steinbeck writes,

This doctor was not of his people. This doctor was of a race which for nearly four hundred years had beaten and starved and robbed and despised Kino's race, and frightened it too (5).

The European doctor then refuses to see Coyotito and illustrates his prejudice against the native Mexicans by telling his servant, "Have I nothing better to do than cure insect bites for 'little Indians'? I am a doctor, not a veterinary" (Steinbeck 6). Steinbeck further illustrates how the Europeans exploit the native Mexicans after Kino discovers the Pearl of the World. The local priest only visits the village to encourage Kino to give a rather large donation to the church, and the doctor finally agrees to heal Coyotito. However, the doctor's healing methods are ambiguous, and it is suggested that he is simply fooling Kino and Juana instead of actually healing their son.
When Kino attempts to sell his valuable pearl, every European pearl dealer colludes to lowball Kino and offers him much less money than the pearl is actually worth. Kino is then attacked and cannot immediately flee the village because his boat is destroyed. The Europeans then send a search party to capture Kino and steal his pearl. Overall, the indigenous Mexicans are exploited and discriminated against by the Spanish colonists, which is illustrated by Kino and Juana's unfair treatment and hopeless efforts to socially advance by selling their valuable pearl.