My BB cover her face with towels too. She loves to play that...but she will take off very soon when the towel cover her face like playing peekaboo...
I think she is kind of like practice her hand control since she just knew how to control her hand in sense . That's why she grab whichever she can and play around
I put a "RICE PILLOW" on top of the towel at the chest of BB when I cover her with the towel...then she will not be able to lift up the towel over her head.