Two Stories
Every race should be interesting to play
Current player thought about rolling up a halfling, but he had a real hard time wrapping his head around why, much less how, to play one. The PHB isn't too descriptive on what makes a halfling, well, a halfling. It's got ability score modifiers, bad art, and some subtypes. So does everyone else.
So, we went looking at AD&D material (the book of halflings and gnomes). We found some art that fit the concept, as well as attitudes and philosophies, seeing their size as a strength in life, mythology, resilience to getting drunk, finding the time to enjoy life (efficiency matters, they're not lazy), the thick hairy feet. We picked a racial name (the "Hin", aka "the folk"). We used the Golarian setting's treatment of halflings (slave nations prey upon them for household labor chores and farms).
And voila, halflings are cool to play for him.
Setting Matters
In a past Curse of Strahd campaign, everyone mutually agreed to limit our choices to human, half-elf, and no more than one elf or dwarf, to fit a Romanesque setting that matched the art and flavor of the area (thinking classic horror, Dracula, etc.) It felt a lot more "real" than if a dragonborn popped in and started breathing fire on everyone. Add in background where players created a story of being related, and we were off. So, put this under an "other." It's not that anyone was drawn to a "human" more than anyone else, it just made more sense for sake of the overall story.