I did play the minigames, and they're nice little distractions. I only played the duck game once, but I don't think I got anything from it. There *seemed* to be a "+1" pop-up on the screen, but I couldn't find anything new anywhere afterwards.
As an aside, the balloon dart minigame seems superfluous to me. If you plan on keeping it, you might consider making it tie in to progression somehow. For instance, it being the same as the "cum-on-tits" minigame, but having a different purpose?