Self-evidently, there is, for the same reason that the USA has degrees of murder.
I think there are a few good reasons to have these, only one being that the recognise different types of culpability. That may not matter from the victims perspective but it can matter from societies perspective.
More importantly though, it means you may be able to convict of a lesser charge where you can't find the evidence for the more serious one, or in cases where the jury would be hesitant to convict on a more serious charge because it seem disproportionate.
I am somewhat surprised though, mainly because of the money angle.