Bilbo with a clumsy attempt to bring health and happiness to
Thorin at his own discretion.
Yes, you can argue 'right or wrong' forever ad-nauseum, especially since none of us have been put to such a test.
That said, the above is an interesting take, with its focus on Thorin and his health and happiness.
I've always looked at it as Bilbo's recognition "The need of the many outweighs the need of the few, or of
the one."
(Star Trek reference, sorry...)
My own take would be "Bilbo with an artful attempt to avoid catastrophe for all". (which happened to include Thorin and the rest of the
dwarves as well, for whom he no doubt had a great affinity.)
And of course it's this very trait of the
Hobbit that brings
Frodo and company to consider 'the need of the many' in the later
events of the destruction of
the Ring against hopeless odds.
Naturally, the 'hopeless odds' Bilbo faced in his decision were of a lesser degree than those of Frodo... but I see the force behind their choice to be the same. (And oddly, why it wasn't so for the rest of the dwarves too, though this brings up another discussion altogether.).
Sadly, catastrophe of a different kind was met nonetheless... and they all rose to the challenge of the far greater need. Thorin is not seen to have a single thought to the
Arkenstone again, in view of the greater danger to and need of the people before him, though prior to that it was his entire world, and he was willing to engage in murder and death to even his potential allies.
Odd, the mental makeup of mankind (and dwarf-kind and elvenkind.)