To easily maintain ratio (of uploaded to downloaded amounts of data) on a private torrent tracker. Due to restricted access (members only), it's pretty safe.
If you're asking about the hosting company, they largely don't care what you do unless someone complains.
Would you think most of torrents are private? So you need to be introduced to be part of them? So if you're introduced, a police investigator could be introduced too, right?
If you're asking about the hosting company, they largely don't care what you do unless someone complains.