Dilt Vs Amio

Why does the ED use Dilt so much when Amio is so easy and safe for AF with RVR. Constantly I have colleagues flogging AF with RVR into cardiogenic shock with slugs of 25-30mg of Dilt at a time. Or completely pee on a forest fire with a dilt gtt. Why isn't amio first line on the sick AF rvr'er super easy to use, super safe, and the gtt is fool proof, don't get it.