It seems to me Mr Restal and Mr Baggins have much in common - they're both 'little men' thrown into danger against their will, and yet they're great survivors. I've just leafed through The Hobbit and found Bilbo complaining about 'this wretched, tiresome, uncomfortable adventure'. They share love for food and drink and for safe, cosy places. (Although I was disappointed to find out that my memory was faulty. I was certain Bilbo got drunk with that wine in the cellars of the Wood-elves and he didn't!)
Then, there's the curious fact that the dwarves enlist Bilbo for their Cause because they believe he's a master burglar. Besides, both Vilvo and Bilbo love toying with language and inventing rhymes and riddles - Bilbo's linguistic duel with Gollum is similar to Vila's with Ultraworld. It's also interesting to observe how they both struggle to overcome their selfishness and cowardice before they set out to help others, although Vila, unlike Bilbo, doesn't always succeed.
N.