Experts do not know for certain why cats lick plastic bags, but they theorize that cats are drawn to the texture of the plastic, the crinkling sound the bags make when manipulated, the lingering smell of food from inside the bag and the chemical scents associated with the manufacture of plastic bags that mimic the smell of pheromones. Some cats also suffer from pica, a disease that causes an animal to crave non-food items.
Since cats are playful creatures, they might be drawn to the sounds and movements of the bag. Licking the bag is one more way to produce sound and movement. Cat owners should avoid leaving plastic bags on the floor or in other accessible areas because cats can asphyxiate themselves or eat the plastic and cause a blockage in their intestinal systems, according to Catster magazine.