The Hobbit, or, There and Back Again Theme of Loyalty

Loyalty in The Hobbit is often based on race. The goblins swear revenge against the dwarves because the dwarves have killed the Great Goblin. The elves and the dwarves have a long-standing mutual hatred because of some disagreement about payment for treasure many generations ago. Family also determines loyalty: Fili and Kili die beside Thorin because he's their uncle.

But this leaves us with the question: what generates loyalty between people who are not connected by blood and family ties? What kind of loyalty exists between Bilbo and the dwarves? Do they feel this loyalty equally? And how about Gandalf: what loyalty does he feel toward Bilbo and to the dwarves? How do these different characters prove their loyalty to one another?

1. Can we find a difference between loyalty out of duty and loyalty out of friendship? How loyal do the dwarves seem to be to Bilbo? And how loyal is Bilbo to the dwarves?
   
2. Is there any reason given for why Gandalf is so loyal to Bilbo? Do you find Gandalf's relations to the different characters of The Hobbit well-developed?
   
3. The line between good and evil is pretty well-maintained in The Hobbit. Men, elves, and dwarves = good (mostly). And goblins and Wargs = bad. But do we see any loyalty among the "bad" peoples – the goblins, for example? Is loyalty a trait that solely belongs to the "good" folks? Which groups in The Hobbit seem to feel the most loyalty to one another?
   
4. Bilbo's return to Bag-End to find that his relations have declared him "Presumed dead" could be seen as a kind of betrayal. So could the widespread hobbit belief that Bilbo has gone nuts in the year he spent away from home. Why does this disloyalty from the other hobbits not bother Bilbo? What winds up being more important to him?