Kino fights for Coyotito's health but loses him in the end anyways.Society put a great amount of pressure to have unnecesary items seem necesary.If society had not been so pressuring to be educated,wealthy,and married, Coyotito may have not ended up dead.
La Paz is a rich, "plaster and stone housed" town,where you can live if you have money,are educated,and are married(given the circumstances i.e. have a family,etc.).When Kino tells the priest that with the money from the pearl he will be married,the priest says, "It is pleasant to see that your first thoughts are good thoughts," which only leads him on to think he needs to get married,or should be married. "Kino's future was real...other forces were set up to destroy it," meant that since he was now the envy of others,he feels the need to buy whatever he can,because he had the money to do so and he would be seen as a fool if he didn't.
Since La Paz was such a envy to all that lived in the brush houses, the strain of Kino "needing" to live there too,now that he had the pearl,was great because of society and their drive of wanting to know what happened next. "My son will go to school," Kino says to emphasize that they will be a part of La Paz, and be "accepted".If you are rich,you live in La Paz, and Kino wants to live in La Paz,for this is described as he says, "We will be married...new clothes...a rifle...
Coyotito will be educated ," these all symbolizing a life of those in La Paz.
If La Paz had not been full of "educated,wealthy,nicely-clothed" people,the strain for Kino to be like them would not have caused the same ending.