Weapons : why are they being used when not at war? (White Giant)

Sorry if was asked before, but im secured mode, yet all my missiles and other ammos are being used, and in some cases, i dont even have the vehicule that goes with it!

A side question as well, is there are any weapons(defense) that gives a better ratings than others?(in proportion of money being used of course)

Just like in real life, soldiers expend ammo and missles to train how to use them. So you will always use ammo whether or not you're at war.

Side answer, the best suggestion I can give you is check the documentation. It'll tell you how much each weapon is worth toward your defense index. They all have a different rating.

But why do they use so much?