The Shrine

If you ever defeat a bunch of tough guys wielding some legendary weapons of total destruction, be sure to put these artifacts somewhere easily accessible so those guys can get it back immediately. The battle in the last month or so can all be completely avoided if the legendary weapons were properly disposed the first time the good guys got their hands on them. Better yet, they should just use those weapons as it is pretty clear their enemies are nothing without these legendary weapons.

At least Sasuke has the right idea as he has a large stock of shurikens and cool stuff. It pays to be prepared (and rich) in the world of Naruto.

Applying logic to an anime about an adolescent ninja....

Even Zeromus put a guard over the Crystal Sword. I mean really they should either use these legendary weapons or at least try to destroy/dispose them, but if you can't do that at least put someone to guard these things!