I'm worried about being too specific in my interests for my SOP

I'm interested in theoretical computer science, but particularly in areas of it that I think have tangible practical relevance. In my intro I talk a lot about Algorithmic Game Theory -- I think this subject is very cool and has many applications. Though, this is a relatively new field and it is rare to find faculty working on it. I'm worried that by talking about this in my SOP I will cut off my chances from schools that don't do this type of work, even though I am also open to other things.

Every sample successful SOP I read has focus. They talk about an interest they have that draws them toward graduate school. For me, that's Algorithmic Game Theory, but I don't even know if I should talk about it since no one really does it, and I don't care about it enough to narrow down my list of schools because of it.