Ok, fine. But how many people out there that casually surf the web do you think actually understand that? As far as they are concerned the address of the site is its "name". The vast majority of people have no idea how to do that. My parents, for instance, can surf the web and google pretty well...but they have absolutely zero idea about I.P.s. This is true for most people surfing the net these days. The fact of the matter is that this materially shuts down the site for the vast majority of people that don't happen to be techies or network admins.
Besides, the point isn't that there is a workaround, the point is that the gov't is seizing websites with no due process AND by the wrong agency.