Because Bungie is lazy as fvck. There are only a handful of bounties, patrols & public events in the game and they really haven't changed since the beta. That shit is fvcking pathetic. So many things they could do here and doing so would go [b]A LONG[/b] way in breaking up the game's monotony. Things like: -rescue the captured guardian -find the lost item -shoot down the enemy drop ship -repair & defend the downed guardian ship -infiltrate the enemy base & retrieve the stolen artifact -win a sparrow race -retake the enemy controlled area -steal a fallen tank -apprehend an enemy captain -complete a strike without using a primary etc, etc, etc...