They're not certified for spinning
Does the aircraft know it's not allowed to spin?
Why do you need military aviators to fly them?
Because they are undertaking military operations, would seem like a fair answer.
It is a really easy and benign aircraft to fly
In a purely civilian environment, yes.
And what do you suggest the 100 hr wonder aircrew do should they encounter a threat? Tell Terry that they are taking their ball home?
BTW, you've not answered my Q above, though anyone using the search function already knows the answer.