I would think that gay people are the bearers of culture because culture requires a type of sensitivity that straight people can't really attain. If you think about it, I believe it is reasonable to say that the orientation itself forces you to face certain things that make you much stronger. To be openly gay, or even to come out to friends and family takes an enormous amount of courage and inner strength as well as a certain amount of sensitivity. Those three factors work well to give you an ability to see the beautiful parts of the world and to want to add to that beauty.
This may not be true for all gay people, and I don't mean to stereotype here, but the openly gay people I have ever encountered have been like that. I have an open mind because I see friends and foes not because of what group someone is in, but if they are mean to me. I have never encountered a gay person who was mean to me. I'm sure there are gay jerks out there, but I know enough gay nice people that I would know those people are not the norm. Plus I look at each person as an individual and not as part of a group. I don't believe in any ism, I give people a chance until they prove they don't deserve one.