I think that claiming that is just making the confusion worse. Sure, you could claim that our preferences about "moral" situations are different from our other preferences; but the very feeling that makes them seem different at all stems from the core confusion! Think very carefully about why you want to distinguish between these types of preferences. What do you gain, knowing something is a "moral" preference (excluding whatever membership defines the category)? Is there actually a cluster in thing space around moral preferences, which is distinctly separate from the "preferences" cluster? Do moral preferences really have different implications than preferences about shoes and I've cream? The only thing I can imagine is that when you phrase an argument to humans in terms of morality, you get different responses than to preferences ("I want Greta's house" vs "Greta is morally obligated to give me her house"). But I can imagine no other way in which the difference could manifest. I mean, a preference is a preference is a term in a utility function. Mathematically they'd better all work the same way or we're gonna be in a heap of trouble.