Agreed. This is a "feature" I will never ever use. Completely pointless and stupid.
And what if we are able to make our own? Something more advanced then just this? What if this was just a sample, an easy to make test that will lead into better shadows and lighting like we see in shader mods? What if we can change what is used with command blocks for custom maps? Or custom potion effects?
Useless? I think not.