Hey,
There are multiple answers to this question. There are many people out there who are wishing for hosting, but there are people that need to run torrent trackers and managers on the hosting. Many hosting providers don't allow the use of torrentflux, or such associated scripts. The torrent's don't have to be illegal, as many torrent's are actually legal. Once again, when you are looking for something like torrentflux hosting -> Check with your hosts policies first.
Regards,
Joe