I ageed there needs to be some form of outcome... but if nothing else it gives you the player a ROLE PLAY OPTION. First time I med the mind controlled fishermen I accidentally got into a fight with them, so I used knock out, because I didn't want to kill them.
After that you never really interact with them, so there it was a great roleplay option.
In town, yeah there it's a bit iffy, but you should be able to use it to get out of combats where you don't want to kill someone. Although it shouldn't get you off the hook, they might still dislike you.
Against the Goblin that Wyll want's to interrogate, knocking him out should yield a conversation option.
Using Knock out to steal from people: That's not the intended use for the ability in DnD, so don't expect it to work.
Roleplay option seem to me like an excuse for bad game design. I'm playing a video game, and I want the game to react to what I do in it, not pretend he reacted. We shouldn't give Larian any break when they implement half baked broken mechanics
