I'm certainly one of them.
I post here somewhat infrequently now, so I don't really feel justified in having one. I mostly just interject my opinions into news articles nowadays, so it's not like I'm really contributing much to the community as-is.
Others probably feel the same, or are just lazy.
Leaving your opinion in news articles is contributing to our great community, and it is appreciated, regardless of how much or often you post.