We all know the set up; Thorin and Co. enlist Bilbo as the lucky 14th member of their party. Plus, they wisely foresaw the value of a sneaky guy in procuring a treasure hoard. But why exactly were there so many dwarves?
In order of appearance, here is the roster of Dwarves and their primary contribution to the adventure:
Dwalin--The first dwarf to arrive at Bilbo's house, he is the first dwarf to arrive at Bilbo's house.
Balin--Dwalin's brother, he is the oldest and wisest of the dwarves. He is also their go to look-out man.
Kili and Fili--Twins, they are the youthful ones. They are good for doing any dirty work that required strong arms and sharp eyes--except being the lookout, which was old man Balin's job.
Dori--On his shoulders fell the responsibility of carrying Bilbo whenever the hobbit was unable to keep up with the pack or climb a tree or grab an eagle.
Nori--There is no evidence to support the existence of Nori.
Ori--Conspired to gain a double share of treasure by occasionally speaking in a funny voice whilst wearing a Nori mask.
Oin and Gloin--Cousins to Balin and Dwalin, they carried the tinderboxes.
Bifur--Kept Bofur company
Bombur--Fat and weak-willed; he sleeps a lot, needs to be hoisted on occasion, and is manipulated into assisting Bilbo's plot to betray Thorin.
Thorin--Ostensibly the leader of the venture, in reality he always defers to Gandalf or, in the wizard's absence, relies on Bilbo to solve any problems that arise.