Character Role Analysis
To say that all Socials are antagonists would be an oversimplification. "Social" (in this novel) seems to refer to people like Cherry and Marcia as much as the boys who aren't involved in the violence and bullying.
It also refers to the people (like Bob) who antagonize our protagonist, Ponyboy, and his friends. Socials as antagonists might also refer to people who use wealth, power, and privilege to gain unfair advantage or power over others.