The Hobbit - Chapter 19 - The Last Stage

[Texadan]

The trolls' gold adds to the hobbit's wealth, though I remember reading (and can't find the exact reference now) that he later gave it away, feeling that it was not his to keep.

From TFotR, "Flight to the Ford"...

'There!' said Merry. 'That must be the stone that marked the place where the trolls' gold was hidden. How much is left of Bilbo's share, I wonder, Frodo?'
Frodo looked at the stone, and wished that Bilbo had brought home no treasure more perilous, nor less easy to part with. 'None at all,' he said. 'Bilbo gave it all away. He told me he did not feel it was really his, as it came from robbers.'

It's interesting that to everyone else Bilbo was "the thief" yet his regard for wealth was less than avaricious. In this last chapter he tried to give all the trolls' wealth to Gandalf but Gandalf insisted they share. Perhaps watching the effects of gold on Thorin made him realize that his wealth was something to be used and shared, not hoarded.