Venat, how about you visualise this; You're in a room cramped full of people, all wanting to be known to the world. You have not recorded a single name down, and after you have recorded, you must go and tell those people that they have been recognised. By your logic, you decide to only take their first names. Ok, so you did it pretty quickly! You got mostly everyone! Time to tell them that they're registered...oh crap. Which John was it? Why do I have eleven Clouds? Which of those five Emily's was a hume? In the end, utter chaos.

Now, if you had surname; the roomful of people still exists. You record all the names down, but it takes longer to write them. But when you go back to tell them, voila! Easy, you're John Wannabe, and the guy next to you is John Wassup. Oh, hi Cloud Arnold, sorry, you were Cloud Cambridge. So YOU'RE the hume Emily Bricks, I got confused between you and the elezen Emily Tarturu.

Which one would you choose? Your choice.