A good question indeed. One reason this novel has remained so popular with teens is its examination of the elements found in high school society. They don't seem to change very much, if at all. The socs and the greasers in the novel are subcultures in their school society, largely as a result of their economic and social backgrounds. Furthermore, they mirror their parents' roles in the greater society: the advantaged vs. the disadvantaged, the powerful vs. the powerless.
Both groups do demonstrate some counterculture traits, but in different ways. The greasers reject the social and academic standards of their school, but perhaps they do so only because they have been rejected first. ("If you don't want us, we don't want you either.") Their poverty and family backgrounds have forced them out of the mainstream. In embracing the values of a social subculture, they feel valued--at least by each other.
The socs form a subculture within high school society, the "stars," but they can be seen as a limited type of counterculture, also. They drink, break the law, and cause destruction, rebelling against adult authority and community standards. As a counterculture, though, theirs seems to be one of youth in general in relation to adult society at large. Because they are children of privilege and the stars of their school, they escape the kind of punishment that is reserved for the greasers.
Great question! The greasers and the socials are both subcultures of the larger culture of high school teen-agers in their city. A subculture is by definition a smaller culture that is part of a larger group, but as a subculture it has elements that set it apart from the larger culture. High schools are hotbeds for breeding subcultures; as long as there are high schools, there will be cliques and groups. Teen-agers may identify with more than one subculture, but they generally tend to gravitate toward one in particular.
The socials are actually the avatars of the larger culture of the high school. Sitting atop the socioeconomic chain, they enjoy status not only among their peers but also with adults. Teachers and parents have always favored the quarterback, the pretty cheerleader, the honor student. The social are part of the established order. The greasers are the counterculture, the opposite in many ways of the socials. The greasers don’t care about grades and sports and social life of the school. They are several rungs down the socioeconomic status barometer. They rebel against the restrictions of the adults.