It's what I thought and my main reason for not using Roon in the first place. I already have JRiver and it does both music and movies nice enough for me to not want to replace it with another piece of software ... not to mention that it's fairly inexpensive in comparison to Roon.
But also important to me is that it allows me to have both my music and movie libraries within one location and one piece of software which is convenient. I also stream a lot of stuff off Amazon Prime since my 2 channel system is also our main movie watching system and Tidal is also running about 10 hours a day around here so I need internet access. I realize you can use Tidal within Roon and it has better implementation than JRiver does, but the Tidal app is also decent enough for me as well.
Got to be user friendly in my house as my girl has a hard enough time just turning all the equipment on and switching my audio/video and its different sources (TT, PC or Cable)

, let alone having to browse through a bunch of different software apps to find movies or music, etc. and more than one PC as an additional Roon only source is just out of the question.
If Roon ever jumps into movies (which is very doubtful) I'm there (though I still wouldn't use the OS portion unless it at least had a browser), but until then JRiver will hold me over.