Middle Earth: Sunset of the Fourth Age
“Hobster” is short for hobbit mobster. As this implies, it refers to members of any of several organized crime families of city-dwelling hobbits. There are a few in the capital city of Isengard, and probably in other larger cities throughout the United Kingdoms.
By and large, the hobsters are a relatively stabilizing influence on the crime world, and in some cases even serve to protect neighborhoods from worse forces when the representatives of the law are few and far between.