On some occasions, when your hands are not empty and you try to do something that ideally needs empty hands, you are told you can't until you free your hands. Trying to climb a ladder is a prime example of this.
On other occasions when your hands are not empty and you try to do something that ideally needs empty hands, the game empties your hands for you (sometimes with results that can be considered irritating or comical depending). Removing clothing is a prime example of this.
I personally would prefer for this general situation (hands are not empty and you try to do something that ideally needs empty hands) resulted in a consistent result. Which is up for debate (though I prefer being told I need to free my hands) but I personally feel it would be a noticeable enhancement to the game. I think having consistency helps make the game easier to pick up and play well.