Conversationalists will want to preserve ecosystems, even where those ecosystems are already well studied by science, even when the ecosystem contains no sentient beings (plants, fungi, microbes), even when destroying the ecosystem has many advantages for humans, because they think the ecosystem is intrinsically valuable independently of the effect on beings with feelings, values, and preferences.

Some looser examples...

Pro-life advocates say that beings without preferences have rights by virtue of future preferences. Not all of them are religious.

Hindus treat books (all books in general) with reverence because they are vehicles of learning, despite not necessarily believing in deities.

Many social conservatives report being unwilling to slap their fathers, even with permission, as part of a play.

The classic trolley problem implies that many people's moral intuitions hinge on the act of murder being wrong, rather than the effect that the death has on the values, feelings, and preferences being morally wrong.

Of course, if you are a moral realist, you can just say that these people's intuitions are "wrong"...but the point is that "feelings, values, and preferences" - in a word, utilitarianism - isn't the only guiding moral principle that humans care about.

And yes, you could argue that this is all a deity's preferences...but why did they decide that those were in fact the deity's preferences? Doesn't it hint that they might have an underlying feeling of those preferences in themselves, that they would project those wishes on a deity?