Good vs. Evil Quotes in The Hobbit, or, There and Back Again

How we cite our quotes: Citations follow this format: (Chapter.Paragraph)

Quote #1

[Elrond] took [the map] and gazed long at it, and he shook his head; for if he did not altogether approve of dwarves and their love of gold, he hated dragons and their cruel wickedness, and he grieved to remember the ruin of the town of Dale and its merry bells, and the burned banks of the bright River Running. (3.35)

The purpose of this quest is not a black-and-white case of good vs. evil. Sure, the enemy is an evil, murdering dragon. But what the dwarves are seeking more than anything else is treasure – as Bilbo points out much later in the novel, the dwarves have thought of "no way of getting rid of Smaug" (12.33). In a book where there are good races and bad races – the elves and the goblins, respectively, the dwarves are probably the closest things we have to a moral grey area.

Quote #2

[Bilbo] must stab the foul thing, put its eyes out, kill it. [Gollum] meant to kill him. No, not a fair fight. He was invisible now. Gollum had no sword. Gollum had not actually threatened to kill him, or tried to yet. And he was miserable, alone, lost. A sudden understanding, a pity mixed with horror, welled up in Bilbo's heart: a glimpse of endless unmarked days without light or hope of betterment, hard stone, cold fish, sneaking and whispering. All these thoughts passed in a flash of a second. he trembled. And then quite suddenly in another flash, as if lifted by a new strength and resolve, he leaped. (5.119)

Bilbo pities Gollum and so, even though Gollum "meant to kill [Bilbo]," he can't just stab Gollum without warning in the dark. Which creatures does Bilbo think it is OK to kill? Does Bilbo make the right ethical decision here?

Quote #3

Then Bilbo fled [with the cup]. But the dragon did not wake – not yet – but shifted into other dreams of greed and violence, lying there in his stolen hall while the little hobbit toiled back up the long tunnel. His heart was beating and a more fevered shaking was in his legs than when he was going down, but still he clutched the cup, and his chief thought was: "I've done it! This will show them. 'More like a grocer than a burglar' indeed! Well, we'll hear no more of that." (12.17)

Bilbo's still trying to prove himself to the dwarves even now that he has gotten them all the way to the Lonely Mountain thanks to his wits and good luck. Obviously, that line in the first chapter that Bilbo looks "More like a grocer than a burglar" really smarts. Like the dwarves, Bilbo doesn't seem to be thinking of his quest in grand moral terms. Given that this quest doesn't seem to be about good vs. evil exactly, why do you think Gandalf has chosen to get involved?