I did actually mean look at it periodically for a while and check out some of the sites that come up. You can't really take a single snapshot for a single day and draw any conclusion from it.

That's like saying there haven't been any IPO's today, so IPO's aren't possible.

Also it's probably slightly rarer to see profitable ad-supported websites actually come up for sale, since often they take nothing to run, so people hang onto them.