The 1/2 fragments is ok since is a daily activity. The point is that the packs doesn't seem to be linked in any way to your rank (I'm anbu atm and i get chunin packs) and the number of ninjas you can get is too wide.

This event shows people greed and uncaring about others too. How many times do you see surely won matches where the enemies don't let other people kill some of their ninjas even if is of no harm to them?

Maybe you don't understand the situations I'm talking about.

When you are left, lets say, with 3-4 ninjas at high hp on team 1 and your teammate have 4 ninjas close to die and your enemy is left with one single, lets say, tenten gnw that can fire her mystery, if you use lets say a very long combo chain with relatively low damage or a mystery with a long animation you surely lose more time than letting the enemy tenten land her mystery, kill the 4 ninja of your teammate and then die by your 3 standard attacks.

And if that guy have the chance to kill those 4 ninjas by hoping in your mistakes or in a delay of the actions why should he retreat when the feature rewards also kills? Should he do it because takes for granted you won't make mistakes or you won't have a distraction that let you delay your actions? In this specific case is you only that harmed him by wasting the same time you would have wasted if he fired his mystery.