Am I the only one who doesn't get befriending someone just because you both might be LGBT?

Earlier today, I was making a delivery to another department and the receptionist there was all chatting me up, like she does sometimes. At one point, I just made a passing mention of my wife and she was all intrigued, lol. "Oh!" she said "You have a wife?" I was a bit puzzled and responded with a rising "Yes?" She must've thought I was offended or something, because she then said "Not that I have any problem with that. It's just, I'm married to a woman too," all gleefully. I responded with "Oh, nice," but what I really wanted to say was "Okay, so what?" Now she's been being even more friendly and chatty with me, all because we both happen to be married to another woman.

My assistant Bryanna was the exact same way when she first started working here. She too heard me mention my wife and got all excited, proclaiming she's a lesbian and that it's nice being able to work with fellow members of the LGBT community, lolwut. But I just don't understand liking someone just for having the same sexual preferences as you. So we're both attracted to other women! Who cares? To me, it makes as much sense as two straight people becoming friends just because they're both heterosexual. Maybe it's just me and being out of touch with my inner gay pride, lol.