In Chapter 7 of The Outsiders, why doesn't Randy fight in the rumble?
Randy decides not to fight in the rumble because he's come to the realization that fighting gets you nowhere. In his conversation with Ponyboy, he admires Ponyboy and Johnny's bravery at saving the kids from the fire. He tells Pony that he doesn't think he could have done it, he probably would have let the kids burn. Randy says, "I don't know anything anymore. I would never have believed a greaser could pull something like that." He's beginning to see beyond Greaser and Soc, and realizes that Greasers are humans too, and they can be good people. He tells Pony that he's sick and tired of all the fighting, and he's beginning to see that it won't change anything. He says, "You can't win, even if you whip us. You'll still be...at the bottom. And we'll still be the lucky ones with all the breaks." Instead of fighting, Randy decides to run away, yes, because he's scared, but also because he's seeing the bigger picture. He isn't at an enlightened stage yet, where he can grow from it, but he's at that hopeless stage of realization where he doesn't see how he can change anything. So he chooses to leave.
In Chapter 7, Randy Adderson has a conversation with Ponyboy where he tells him that he has decided not to fight in the rumble. After the death of his best friend, Randy has come to the realization that violence is useless. He explains to Ponyboy that it doesn't matter which gang wins the rumble because nothing will change. Essentially, Randy understands that violence is not the answer to their problems. Although Randy does not have a definite answer, he feels that his best option is to run away. Randy tells Pony that if he doesn't run away he will be "marked chicken" for choosing not to fight in the rumble. Randy simply does not want anymore of his friends to die and refuses to engage in senseless violence. His decision to not fight in the rumble depicts his maturity and developed perspective.