You respond to the posts only if you find it worthwhile. When creating them, a person cannot guarantee if he is putting up a content to stimulate discussion. But only through trying will you ever be able to improve the content you share with the rest. Lets just say its a work in progress and you can easily weed-out irrelevant posts .
Personally, to me its not ok. Even I have a few discussion which never got a single reply . If i am unable to generate a discussion then i failed at putting up something useful. I would simply go back to data/information collection and prepare better for the next one.
But you got to start somewhere to make that happen. We are only trying to promote an environment where everyone is trying to share some information with the rest. In time the quality will improve too.