It's not like there's an abundance of heterosexual relationships either though.
I could understand the frustration if everyone was pairing up, but frankly, the world is more or less asexual or open for interpretation.

Between the completely equal player marriages, and the WoL-sexual npcs, I don't see a problem.
There's also the possibility of Gaia and Ryne, not to mention the championing of unconventional gender roles in the pixies and dwarves.