Collectors are one of the only types of NPCs you find as often outside of a town as you do inside.

Collectors are one of the only types of NPCs you find as often outside of a town as you do inside. Collectors are NPCs who, for whatever personal reasons, need large quantities of certain trophy items that fall from the bodies of enemies that you slay in the wild. Many Collectors offer a wide variety of somewhat powerful weapons and other items in exchange for these trophies, while a few can give you high-grade magical armor that you won't find for sale at a Crafter. Even if you don't have a great need for whatever reward the Collector has to offer, you can almost always turn a profit selling that reward later, trading it to a friend, or giving it to one of your own alternate characters via Xunlai storage. Collectors are identified by the suffix [Collector] after their names. Don't be surprised to find them in the most unlikely and inhospitable landscapes. http://www.guildwars.com/gameplay/exploring/townlandscape/