Animation-controller hierarchy (controller animating child, instead of "this")

Using Blender, I have a turret-base, barrel and a recoil animation playing on the barrel.

In Blender the animation shows to be on the Barrel itself, but when importing into Unity I need to put the animation-controller on a parent of the Barrel. This animation-controller will then animate the child named "Turret_X1_Canon".



Setting it up this way in Unity does work, but I'm just wondering why the controller has to be in the parent (especially since in Blender it shows the animation on the barrel itself) instead of the animation being applied to "this" (the object on which the controller is) directly. Basically it feels like there is "one unnecessary child".

Any ideas if this is possible, or is this the generally accepted way of setting up animations ?