Indeed, cats do like to be confusing and contrary.
My cat will only eat Whiskas brand kibble. He won't eat anything else, and won't touch his food if there's anything mixed in it, though I do at least try alternate brands every so often, from expensive to cheap.
That was true until about a week ago. I bought a bag of Purina indoor formula, which he's never liked before.
Now he refuses to eat his Whiskas, and tore open the bag of Purina (a first, he has NEVER torn open a bag of cat food before, or even paid much attention to the bags).