For what reasons is much of the first chapter devoted to Boo Radley?

I believe that Boo Radley is mentioned so often in the opening of the novel because he is an essential factor in the growth of Scout/Jem's maturity throughout the novel. As the feared scapegoat of the indolent society, Boo's inferiority (as labeled by society) relates directly to the harsh, supercilious views Maycomb imposes upon African-Americans who have done nothing.

Atticus tells the children never to kill a mockingbird because they have done nothing but provide lovely melodies for people to listen to - because they are innocent. Boo Radley and the African-American community both symbolize mockingbirds in that they have done no wrong deed yet are blamed for all the failures of society. The children, believing the unlikely rumors exchanged throughout Maycomb, are at first frightened by this mysterious figure. Their childish curiosity leads them to accept a number of dares, each involving Boo Radley (touching the Radley Place, sending him a special message through the usage of a fishing pole, etc.). However, as the novel progresses and the trial of Tom Robinson arises, the children are able to relate the similar injustices both Tom and Boo are forced to face because they are different from the typical white mold of society. THe society prefers to remain loyal to their southern traditions and reject those who act as iconoclasts to their quintessant society.