Yes, on occasion. And on occasion I read someone else's post that seems very deserving of a response and no one has responded to it.
I figure when that happens, the post either didn't strike a chord with people or else they didn't feel they could reply positively - though then again, people do post their disagreement with something.
I often want to just reply with a thumbs-up to something someone posted, but then I'd be ignoring all the other people's replies. So I rarely do that unless I have something of my own to add.
However, when I start a thread, I try to acknowledge every reply. Then I worry that I'm overdoing it and should back off and let people talk to each other without me commenting on every post.
So it's a fine balance. I think the only time lack of response would bother me is if I think I had a brilliant idea or insight and no one acknowledged it. Most of my ideas/insights aren't of that caliber, though, and most of the time I suspect I'm stating the obvious. Too obvious to comment on.