My vet refers to the Whiskas and Felix brands as the McDonald's of cat food because they are so highly processed with very little meat, as Dollymarie explained. I am sure such highly processed, supposedly 'tasty' cat food plays a significant factor in the rise in cat obesity.
I never eat McDonalds so I refuse to feed my cats such poor quality food (not that they'd touch it anyway). Pet stores stock a much larger and healthier range of cat food than most supermarkets - ranges like Applaws and you can get wet Hills too. My cats don't like a diet of exclusively dry food (as my vet advises - she would prefer them to have just good quality dry food, I mainly use Science Plan). Quality food costs a bit more but surely it's worth it to have a healthier cat?