Readers Groups? No, Just Writers

I've joined some groups at Goodreads to try and promote Killer of Killers, and there's a couple of Martial Arts groups over there, and an Action/Thriller group, too, and both groups have a lot of members. So I was hoping being there would prompt an interest in my book. Nope. I'm finding out that most or maybe even all of the members at Goodreads aren't much into reading other people's books. They are practically all of them writers with books of their own to promote.

I really doubt much more than one or two of them have any interest at all in reading someone else's book, let alone buying one. Hey, I'm not judging, because I'm one of them. I spend 100% of my spare time writing, not reading. And so I can conclude that they do, too. It's back to the old conundrum--more writers than readers---at least in the groups I join. How to solve it? Find groups that are readers and not writers. That's all. But where are they?