Also, they are meant to be used that way. When people recommend those applications to friends and relatives they are meant to be used for copyright infringement.
I'm not agreeing with what was done here, but there is a qualitative difference between a torrent client, media player, etc, and the popcorn time applications.
Edit: yes, you can hit a movie streaming service with your web browser by navigating to a URL. Have a cookie. But that requires previous external data and thus is not "clean" install.