Why do cats need wet food?

Note that most store-bought cat food is dry, also known in the United States as Kibble, or in the form of a wet can. Some manufacturers sell frozen feed and premix products to cater to cat owners who make their own cat food. 

Dry Foods (8-10% moisture) are usually cooked by extrusion under high heat and pressure. Fat will be sprayed on foods to increase palatability, and other trace ingredients, such as heat-sensitive vitamins, which will be destroyed during the extrusion process and may increase. Canned or wet grain (humidity 75-78%) is usually 3 ounces (85 grams) , 5.5 ounces (156 grams) , and 13 ounces (369 grams) in size. Will also be sold in aluminum foil bags. Vegetarian and Vegan cat food is sold, and vegetarian cat food must be fortified with nutrients that cats are naturally carnivorous and can not synthesize from plant foods such as taurine and arachidonic acid. Some Vegan cat food brands are labeled by their manufacturers as following AAFCO cat food nutrition standards.