We were standing next to the galley, waiting to board, when I saw a woman take the pillow from my wife's seat (11K) and go back to her own seat (10D), where she proceeded to make herself comfortable with two pillows. I wandered over and asked for it back, pointing out that she could ask the cabin crew if she needed a second pillow. She handed it back, grudgingly, with no apology. (I assume she did not want to inconvenience her husband, or one of her children, by taking their pillow). I also assume that by taking a pillow from the opposite side of the plane she thought she would be far enough away from the crime scene.
Is pillow theft a common occurrence???