As Per DM Vivec's post here: viewtopic.php?f=37&t=42313
The problem people have, when it comes to reporting pickpocketing, is that you don't know WHO pickpocketed you, unless you have really high spot. Not to mention they can also pickpocket you from stealth, meaning that they don't need to interact beforehand, to 'PvP' steal someone's coin. And lately, I have noticed an uptick on pickpockets around the place, as I've been stolen from multiple times in the last week, much to my character's Chagrin.
Given that reports require you to know the name of the character, or person's login name, in order to put forward a report, while I certainly agree reporting is the best thing to do... if you don't know the name, you can't.