No, the £29.99 subscription allows you to access online or with the app, to watch it on TV you need Sky or VirginMedia and then pay whatever their rate is at the moment. I've viewed it on TV by connecting the PC, haven't tried casting yet.
It's worth it to keep up with the U23/U18 games and the Man Utd Women's team if you follow it, and I sometimes watch full matches when they are re-broadcast the following day if I've missed a match because of work commitments. It obviously doesn't broadcast anything critical of the owners, but it's not censored or sanitised either. It's a house channel, so, like any house channel, it's there to support the club.