Or it could be that perp is a straight up loner with almost zero friends or family. Most serial killer's, if that's what we have here, are complete loners who are left to their own vices.
It's also crossed my mind that suspect may have already silenced those who would have come forward to identify him. Imagine his surprise when he saw those still shots of himself all over the news! You can bet he wasn't expecting that.
Which leads me to my second theory. This guy may have killed himself already and is rotting away at home waiting to be discovered. I know it's rare that people like the this commit suicide but, given the unique circumstances in this case I think it's highly probable. After all, most serial killers think they'll never be caught.