However, this comment by @nailer is not the first one that asks about a demo. Others have asked for the demo link too despite the very first badge on the README being a "view demo" badge. That made me think that perhaps the "view demo" badge is not an optimal way to draw the reader's attention to an important link.
I guess, the readers ignore these badge-based links either because they associate badges with status displays (build status, coverage status, etc.), not links or because these badges are overused in many projects which could cause our minds to ignore them as noise.
In any case, I have added a text note to the README now, that says, "Note: A demo page is available [here][Demo URL]", to ensure that it becomes harder to miss the link to the demo page.