I think people look at this the wrong way. It's not about catering to a game's gay population, but servicing players who play a main the same sex as a friend or significant other. Usually what happens is they release a marriage quest that kicks ass, and people grumble how its only applicable for a few people. The actual gay population of the MMO is about the same as in rl, probably close to 6% of the players, so its generally not a factor enough to drive change.

If DOMO online had a simple one-time ceremony with none of the perks that it looks like this marriage quest has, you wouldn't see enough demand to change it.