Creating a sense of urgency right away will help Roosevelt make sure all of the different groups he is addressing are listening right away. When the stakes are high, people tend to pay more attention. This way, they will be focused for when he addresses them or their cause specifically, and more general statements he make will feel more important because the people will apply them to their own causes.
What is he waiting for? I believe it might be a fight or a drug deal. Lol. Probably not the second one though. :P
Ponyboy follows the Greasers because he's a member of the gang and because he doesn't fit in with the Socs.