Doesn't the fact that they [b]have[/b] orders mean that they [b]are[/b] being treated like military cadets. 

Also, military cadets have normal classes too. That's how military school works. DWMA is just an advanced military school, training child soldiers while keeping them competent enough in other fields of study so they can function in the world.

And I don't recall them directly disobeying orders often if at all. The only thing I recall is Death the Kid stopping to turn to and run after the sky because it was perfectly symmetrical but that love of symmetry comes from his nature as a God Of Death, beings dedicated to order. Eventually, he realizes that symmetry isn't everything but he still treats the ideals of order and the world's safety with the utmost  importance.

Plus, if we say having an idiosyncrasy means you aren't a professional than everyone in this story is garbage.

Between the lecherous teachers

The Scientist who dissects people when they sleep

The school Nurse....

And the Secretary that body slams people to the ground

This world is just full of crazies, we have to adjust our standards and views of behavior for the universe we're in.


EDIT: And yes, I will draw you a picture.