The conservative political commentator and humorist P. J. O'Rourke has asserted that one does not solve the problem of poverty by giving money to poor people. Although this is a point most often made by conservatives, there is widespread agreement across the political spectrum that social issues will often prevent a poor person from benefiting from sudden wealth, such as a lottery win. The pearl Kino finds is his lottery win, and it brings him nothing but misery, due to the corrupt society in which he lives.
The pearl buyers represent the greed of a capitalist system which will never allow the pearl divers to receive a fair price. This system marks Kino out as a victim the moment he has something of value, and he is constantly pursued by thieves. The doctor, in particular, symbolizes a system in which life is dependent on money. It is ironic that, of the two main events at the beginning of the story, the first, which appears a tragedy, turns out to be harmless, while the second, which seems a blessing, is a curse. The scorpion which stings Coyotito does no real damage. The child simply recovers. It is the discovery of the pearl that eventually kills Kino's son by making the family a target.
It is significant that when Kino and Juana first take Coyotito to the doctor, they are unable to see him. The doctor is protected by his wealth, his walls, and his servants from everyone he does not wish to encounter. This is because he is part of the corrupt system, insulated by money. Kino has no such protection, meaning that the social issues of poverty, crime, and corruption impact him directly as soon as he has something worth stealing.