Is full Auto necessary?
There are perfectly acceptable reasons to have or not have that capability. To have it available and no desire (or need) for it is better than not having it and needing it.
Now, I am a civie, have been since my honorable discharge after fulfilling my 8 year obligation. I own 2 machine guns (a vector arms UZI and a HR M-16), all legal like, both are select fire. (Oddly enough, I don't own a single assault weapon.)
Do I have a need to send a lot of bullets to an enemies direction? Nope, not a bit. Am I waiting for the zombies to take over the world, Armageddon or for the fall of the USA? Nope, not a bit. I actually prey like heck something like that never happens.
Wanna know why I have the need for full auto? Well, quite frankly, because I can and it is fun. I like to have fun. If I didn't like to have fun, I wouldn't have two kids. Not trying to be rude, just honest.
When I go to a range, I am going not because my life requires it, but because I want to have fun. Many people go target practicing for fun, with accuracy being not that important. They shoot as fast as fast as can be. Sometimes using various tricks to accommodate the rapid fire. Why? For the fun of it. There is nothing wrong with that. Life is greater, so why not have fun. Is full auto needed, for fun? Sure, why not.