Lets look at it with faction in mind then. Both factions have at least one pretty race to choose from.
Horde: 71% of characters are of an "ugly" or bestial race
Alliance: 48% of characters "ugly" or bestial (including dwarfs and gnomes) or 32% (excluding dwarfs and gnomes)
What you are ignoring is that the number of western players who would happily play as an ugly/beast race is not negligible. When split into separate races it may seem that the non-pretty are less popular, but that's because there's 8-10 of them to choose from and only 3-5 human like.
One of the reasons why people pick the monstrous races on Horde side is because they are given the misfit role:
"Misunderstood and cast aside, these diverse and powerful races strive to overcome their differences and unite as one in order to win freedom for their people and prosper in a land that has come to hate them. In the Horde, action and strength are valued above diplomacy, and its leaders earn respect by the blade, wasting no time with politics. The brutality of the Horde's champions is focused, giving a voice to those who fight for survival."
Even earlier in this thread someone didn't find it believable that a monster could successfully serve the grand companies and meddle in politics. No matter their culture, advancements or heroic deeds, non-pretty races would be lumped together with beastmen by both player and NPC. But that kind of hardship is precisely what attracts some people to choose those races. I think that if a playable beast race was ever introduced in FFXIV, the story team would have the skill to consider all of this and make it believable.
I would like to emphasize that my criticism for FFXIV races is mainly towards the female designs. With males they did an excellent job. Miqo'te and Au Ra males look borderline beast races already and the rest are very distinct from one another.