The problem would still be that someone has to seed the torrents. Maybe it'd be possible to build a torrent client that signals he has the file available but only seeds it is paid for. Would be cool to have an incentive for seeding but still keeping the unmodified bittorrent protocol below for compatibility. This way infrastructure could emerge by itself mhh
I hope something like this will be built, would love to stream some ecash for a torrent 

 I left out the most important part; the relay(s) would be seeding all the torrents. Probably impractical but This is interesting yes I'll keep thinking more on this

Great idea to get the ball rolling 💪