I’m pretty sure they do it to fly under the radar, since mobile clients are far more dominant than smart TV applications.
And there’s also newpipe as an alternative to Vanced (or rather the other way around, I believe newpipe came earlier), and even a fork with sponsorblock integration. I personally vastly prefer them over vanced/revanced.
A simple network sniffer is enough to figure out what sites the app is connecting to, then you can just block them on the router.
If you are using Android, you can do that easily right on your phone with PCAPdroid, it’s on the play store. No root required.