Radiant Blade (and probably other weapon replacements)

Using a weapon replacement simply replaces the model with a new one - relevant character animations are not changed. The link below is a picture of my marauder holding a two-handed hammer with the 'Radiant Blade' weapon skin.
http://imgur.com/a/lcWQc

Take note that his right hand holds the blade of the sword, and his left hand is not even holding the weapon.

Considering that GGG uses microtransactions for its main source of profit, I expect greater care to be taken. Why not have weapon replacements alter character animations?