probably for the same reason that tens of millions of people don't vote even in a presidential election. When I see questions that get zero answers, I might answer it just to start the ball rolling for that person. You can see from the question statistics that first of all there aren't that many questions being asked, and there are a lot of questions that don't even have a single comment. People try to tell me, that it is my fault, but the statistics prove otherwise.
The stats can be derived by going to answers, and scrolling down to the last entry, with is the hundredth question. Then look when that question was created, and divide that number by 100. Say that was 4 days, than that means only 25 questions were created in that time period.
You can do this filtered, by selecting latest, and then say an area, like Politics, and social. And you will see that average daily number drop significantly.
If hp had a large audience of "Active" hubbers that daily number would be in the hundreds.
del if u wish.