Please Watch the Video
On top of that, he/she probably does this in his/her free time
Edit:And imagine you're developing an unfinished game and releasing it with a clear disclaimer that it's unfinished. (In this case a Demo)
And there's exactly one person like you who writes in the comments that they'll hate your game (and your cat) if there's no update.
It's like playing an Early Access game and complaining that it's not complete.
I love the Game and why he/she is making it.
If you don't like it, just say that, but please don't complain that it's not finished.
Wow, that really made me angry lol