Why did Steinbeck include the first section about life in the gulf waters?

Steinbeck includes the first section about life in the Gulf waters to detail the extreme poverty in which Kino and Juana live; not only can they not afford their own canoe so that Kino may perform his job as a pearl diver, they must use a canoe that is several generations old. This is important, for it gives greater weight to the discovery of the pearl, which could raise them from a meager existence into some sense of security.