There are totally puzzles! This is a neat idea, and I could see it being expanded. Some of my favorite game moments are uncovering the less-expected interactions between objects. Animal Well does some of this!
This reminds me of something I made years ago when learning Flash. It was like Breakout, but instead of bricks there were five mysterious speedometer-like gauges on the screen. The goal was to figure out what the gauges were measuring, and max them all out.