The site is not illegal because it is a file sharing site but if you host or download an illegal file, you are under a federal offense.

Now now. The site itself isn't illegal. Torrent sites in general aren't, and neither are torrent programs.
The content being hosted by the users of said sites, however, in most cases is illegally shared files.
If I was a writer or an artist and wanted to bulk-upload my own personal life's work to a site of that nature to be shared, by all means I'm allowed to do so. That's my choice.
Should the next person, however, decide they want to share their entire CD Collection from various artists, that IS illegal. This gentleman has no ownership other than his own copy of the disks and certainly wouldn't have the permission from the Label and/or Artist to share said works.
There's a big difference ;)
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