With all these seasonal events going on I have been working on my lowbies again which gets me to thinking about some of those interesting characters you run across while questing in those areas. One of them is Renzik "The Shiv". Unless you are a rogue most individuals will have absolutely no idea WHY there is a GOBLIN inside the Old Town of Stormwind. IF they happened to think of it at all they I am sure would assume he was there to be interrogated or sell information, the truth would most likely shock them to the core.
Renzik is Mathias Shaw's second in Command. Yes, you read that right, a GOBLIN is the second most powerful individual in the ALLIANCE's information gathering network. If you can get past your shock you can understand Shaw's reasoning. Renzik has connections both with the Hidden Circle in Ironforge as well as with specific rogues in Darnassus (since they have not seen a need to develop a specific rogue organization). Add to that his more intimate knowledge of the goblin cartels and in this one individual Shaw has someone who can single handily point him in the right direction on useful contacts.
The thing you have to realize is that Mathias is not the one responsible for recruiting Renzik. Rather, Shaw was only able to build on the relationship his grandmother had already while he was a member of the Stormwind Assassins. Shaw provided him with the type of opportunity that would send his fingers itching. Renzik, unlike other goblins is not interested in monetary gain as much as information. He is a top rate thief, it is to him that Alliance Rogues are set to join up with SI:7 and more specifically the all important lock picking. So to be at the center of all the action is just where he likes to be.