Oh for fuck sake, this is getting stupid. The existence of homosexual content in a game doesn't mean its trying to encourage it, only that it's acknowledging the existence of such things. While I do think a game intended for kids shouldn't include graphically explicit sex in it, that is what age ratings are for. You wouldn't (or shouldn't) let an eight year old play The Witcher 2 if you think he or she shouldn't be exposed to nudity and unambiguous sexual content, and that's why the game's rated M! If The Old Republic's rated T, and it doesn't include a lot of sexually explicit content or nudity in it, then that sounds appropriate. I'd think by teenage years the average kid would be ready to acknowledge the existence of homosexuality. Pre-teen age, that's debatable, but by the mid-teens I don't think you're going to be shattering that much childhood innocence with non-sexualized gay characters.
So yeah, I don't think The Old Republic is trying to warp the minds of today's youth if they're giving their game a responsible rating. That puts the responsibility of who sees the game's content on the parents, not the developers.
Oh, and if you're going to compare my opinion on this issue to my opinion on the gay-marriage-Archie-comic-in-Toys-R-Us one, here's the difference I see. The comic being in Toys-R-Us means any underage kid could pick it up and look in it. With the game, there's much better control over who gets access to the content. To me it's the difference between having naked pictures in a magazine behind a store counter and pinning up a Playboy centerfold on the bulletin board in a youth center. Maybe not an exact equivalent, but something like that.