I have found another thread talking about this, but it's closed. This is a topic that has fascinated me ever since I discovered other DLs online. I have spoken to several DLs about this, and they all seem to say it's because gay people are more open to things like that. I have thought about this long and hard, and still can't see this as an explanation.
From my experience the percentage of gay people in the AB/DL is much greater than in other fetishes. I just can't seem to believe that the only reason for this is because gay people are more likely to want to experiment with their sexuality and are theirfore more inclined to explore fetishes like this. I may be wrong, but I can't help to think there is a different mental/emotional link.