I don't know that it's all that strange or uncommon, but my ladycat Angel loves butter, or anything that butter happens to be on. She gets little pieces of buttered toast and maybe a few tiny pieces of butter fried egg during breakfast. Her favorite is if I smear a little bit of butter on the table for her to lick up. I don't imagine it's all that good for her, so I don't let her have very much at all. The nice thing about it is I never have to eat breakfast alone.