In a lot of ways, catfighting is mainstream. If you want to see it, there are many movies with catfights, WWE, pay per view. You don't have to go to the internet to find it. Plus a hundred Yahoo videos. I think the Taboo nature of this has largely faded now which is why you don't see foxy boxing or mud wrestling much. Just isn't that "extreme". But as far as a "special kink" we are a pretty small group. I think you would really need to compare that number to membership on other kink sights to get an idea of scale. For example, if you look at Fetlife.com and do a search for groups using "Catfight" the biggest related group is "Wrestling, Grappling, and Struggle Play" with a membership of 9,504. Of course that includes every crossover group imaginable and is overwhelmingly male vs. male. The largest Catfight specific group is "Catfighting Bitches" with 510 members. There are a total of 46 related groups to catfight. For comparison, do a search for "Breasts". Just like us, kind of a conglomeration group. Some like them big, some small, some a specific race or color, activities, etc. You get 626 related groups with the largest directly related group being "Breast and Nipple Torture" 13,699 members. That means roughly there are 27 times as many people into "Breast and Nipple Torture" than are into Catfighting. Of course that isn't scientific, but it is about as close as we are gonna get without a federal grant.