If it’s not cached there’ll instead be links that makes RD start a new download of that torrent (this can be disabled in Torrentio settings). The reason not to use those links would just be because you have to wait for RD to finish the download, but in either case you’re never torrenting yourself. You’ll see “RD+” above the quality label of streams which tells you it’s from real-debrid, so you’ll always know if it’s not.