Why USA use launchers "for one use"?

[AlexKall]

So the Carl Gustav is NOT a rocket launcher? This confuses me because Germany used the "Panzerfaust Carl Gustav" before the Panzerfaust 3, which is a rocket launcher was introduced.

Its actually both

 

[sunb!]

http://en.wikipedia.org/wiki/Carl_Gustav_recoilless_rifle

We call it cannon in Norway, but I realize the international name is recoiless rifle. Sorry for not checking the proper international name...

Check out the wide array of ammunition for it.

 

[Mohmar Deathstrike]

Its actually both

I was suspecting this. Thanks for clearing it up once and for all!