Because half the time the show writers adopt our names out of respect or because we as a community just come up with good names sometimes. They've adopted the name Button Mash officially for example, and Derpy Hooves is the most famous example where all the writers admitted that this is what the character is known as in the office but they got in trouble that one time because of the dumbass controversy of her name when they actually tried to drop it in the show and since then are more careful about officially acknowledging it. Because "derpy" is apparently offensive to people with real mental deficiencies.
Funny because Snails as a concept is arguably more mean of an idea. His special talent IS being slow, but no "moral guardian" parents complained.
EDIT: And yes I'm aware that often the show adopts names unofficially from the community but then because of legal issues or some other reason later. Bonbon is a perfect example because officially she is Sweetie Drops, but most people agree she will always be Bonbon to us. My point still stands though, there's nothing silly or pointless about this. The effort to name characters as a community is exactly as valid as it has been in the past and we've already done great things before. I don't see a reason to make a fuss over this.
Of course we did almost just come close to naming the Sphinx Isis, which is a completely valid NON-TERRORIST name with its own origin and meaning, but like the Swastika, would have had bad implications in the real modern world, but honestly even if people meant it in the most pure, non-offensive way possible Hasbro wouldn't have dared accepted that pitch from us and I'm willing to bet neither would Derpibooru's staff if it really did come down to that and enough people voted for the meme juice. But I'm not here to revive that argument — I'm saying that these polls aren't perfect, because the community isn't perfect. But I'm willing to bet you'd get the same kind of results from any other forum where bronies would come together to make a decision like this.