Why is social class important to the story

Social class is the basis for the main conflict in the story.The Greasers are "poorer than the Socs and the middle class... almost like hoods; we steal things and rive old souped-up cars and hold up gas stations and have a gang fight once in a while." In contrast, the Socs are "the jet set, the West-side rich kids," who "jump greasers and wreck houses and throw beer blasts for kicks, and get editorials in the paper for being a public disgrace one day and an asset to society the next."