 Yasemin Salgil Demirbash is a professor of veterinary physiology at the University of Prince Edward Island, and she says they're really not out to get you. This is not a behavior which is displayed to punish the owners. Demirbash co-wrote a research paper on why cats scratch, and she and her team found a relationship between scratching and environmental factors like loud noises or kids. So shield the kitty, spare the sofa.