The main difference between the greasers and the Socs is that they are from different social classes.
In The Outsiders, we learn that Socs are from the higher social class and greasers are from the lower social class. The greasers are different from the Socs in other ways than being poorer though. The two groups have set themselves at odds. There is the social club, and the street, and never can the two cross. Most of the greasers can’t stand the Socs, and vice versa. They hate each other on principle, and stand up for one another.
Greasers are almost like hoods; we steal things and drive old souped-up cars and hold up gas stations and have a gang fight once in a while. (Ch. 1)
Pony comments that while he considers himself a greaser and is proud to be a greaser, he does not necessarily love to fight and he would not rob someone for fun or even for the money. He just goes along for the ride. He dresses in jeans and t-shirts and wears his hair long and greasy, because it’s what he can afford and its part of the neighborhood look. That is what he is proud of—being part of the neighborhood, and standing by his brothers and friends. He comments that it is hard to be a greaser though, and that with his parents dead it wears on his oldest brother.
Only Socs. And you can't win against them no matter how hard you try, because they've got all the breaks and even whipping them isn't going to change that fact. (Ch. 1)
The differences between the two groups go beyond entitlement. Greasers live life passionately. They care about each other, because that is all they have. They stand up for each other, and look out for each other. They are fighting for survival, not out of boredom. For the Socs, it is much different. They are just around until something better comes along. While greasers fight because they feel too much, Socs seem to be the opposite. They fight because they feel too little.
Socs were always behind a wall of aloofness, careful not to let their real selves show through. I had seen a social-club rumble once. The Socs even fought coldly and practically and impersonally. (Ch. 3)
When Pony meets a Soc girl, Cherry, at the movies, he is surprised to learn that Socs do have feelings buried deep inside. They do have problems too, although Pony laughs them off. He feels like the Socs’ problems are minor compared to the greasers’. All in all, what he learns from the experience is a little empathy for Socs, and an awareness that they are not all the same, and there might be an opportunity to end the cycle of fighting because some of them are as tired of it as the greasers are. Of course, it will take quite a lot for that to happen, if it ever does.
Pony is different from most greasers. He is more reflective, and more introspective. Even if the endless cycle of rumbles continues, he has the opportunity to use his intelligence and compassion to get out.