D&D is not LotR; RPGs are not books; and things which work for one may not work with the other.
Hobbits are rustic homebodies who shun the world outside the borders of their own lands, and generally speaking avoid anything remotely resembling adventures. They work very well in LotR, because a) they're an idealized representation of the British countryside and its people, and b) they provide a recognizable group of viewpoint characters, much closer to the reader than the Men of Middle-Earth; Bilbo, Frodo & co. are all very unusual hobbits.
In D&D, if you want halfling adventurers to be more common and less at odds with their race than good-aligned drow wandering on the surface, hobbits don't work. Making them family-oriented, opportunistic and both interested in creature comforts and curious, prone to travel or living in safe places among other peoples, you suddenly have a race that you can plausibly see providing numerous small, roguish adventurers.