Well for me, the thing is that labeling different genres helps finding me new stuff to enjoy. When I read for example suicidal black metal, it is not very likely that I will bother to check it out, unless there are some more specific references (to bands) for example. Plus, like Father already pointed out, it's very helpful sometimes to talk about it. A couple of months ago our current photographer asked me if I knew some good black metal bands. But as you might know, it's a very broad genre with a lot of different bands. So in that case, it is good that people get a bit more specific with terms like, in this case, orthodox or raw.
Also, on a positive note: I am officially in a relationship with this Hungarian girl since a couple of days I might upload a cheesy picture soon.