User blog comment:Ocomfv/Theory on the origan of Grimm/@comment-24513473-20141029224643/@comment-25399622-20141030000725

No, but if you want it to be effective at all you probably should have access to your Aura.

"Dust can be harnessed in a variety of ways, but when used in its raw form, its full potential requires both an Aura, and the intelligence to use it, meaning Humans, Faunus and artificial beings, such as Penny are the only ones who are able to effectively use it for combat." - Terminology: Dust

They just can't use it to its full extent (but regular people that haven't unlocked their Auras probably aren't fighting with it).