Why seed a torrent day and night, linking your actual IP to the infringement act, when you can just upload a file to a bunch of file sharing services on a cafe's wifi and post a link on a forum? If your goal is to illegally distribute files without getting caught, real P2P seems like a suboptimal choice for now.

They way I see is that people who upload pirated content to those websites aren't doing for a cause. They do it because they earn "points" when the file is downloaded by a free user. Then, they can use those points to create premium accounts, that can be sold easily.

People won't really care. They just use whatever is easiest for them.

When central storage sites are shutdown other mechanisms will be used for sharing. But why bother as long as it works? You're not locked into a particular site, so there's no reason to use other approaches just because something might happen.