Xbox doesn't have an interactive city like enviroment like Sony will so it'll be hard to make a crew outside of just playing the game.
Sadly the fact that your disc is fucked because of your 360 proves your statement false
Though Halo 3 is fun, apparently not as fun as Call of Duty 4, which outsold Halo 3 in what...its first week? and it got Best FPS of the year. CoD4 rocks the shit.