I know this feeling all too well.
Lucius, especially, often pulled this trick on me. I would arrive home from PetSmart, nearly falling on my face from juggling multiple cases of his favorite Fancy Feast flavor: chopped grill.
Upon serving His Lordship, Lucius would look at me studiously. I was expecting a follow-up expression of gratitude, but instead I thought I heard him say, "Why did you buy this terrible food? I HATE this flavor."
Ah, memories. . . .