I've just found a great point & click adventure game that looks like probably made by Visionaire Studio or Adventure Game Studio.
https://www.youtube.com/watch?v=01AHYg27DuQNow, this game is episodic and being episodic means one chapter should last 1 & 2 hours.
Although, the game itself is completely free of charge. But we can see making adventure games as episodic is one strategy for the developers. Because it's saving times and getting feedbacks easier and stuffs like that.
Now if the game is commercial, then suffering begins. Makers of episodic adventure games (someone call this game as casual) are now part of victims as well.
I've just researched to determine existence of short adventure games. That's all. Let's wait until Steam's policy's change.
By the way, the game looks pretty nice.
http://store.steampowered.com/app/378300/