I am all kinds of :-( about making Earth Day a religious holiday, because it isn't. It was very clearly created as a secular call-to-action day -- not even a holiday, really! So while I am all in favor of having a day set aside to reverence the earth and the 7th Principle, I do not like conflating that idea with Earth Day. It's not our day. It's for everyone. We should not co-opt it.

I have a "Famous Unitarian Universalists" t-shirt, and when I got it, I spent a good hour or so going over the listed names and saying, "Not actually a Unitarian," "Left the denomination," "Not actually a Unitarian," and so on. It was funny in a painful way.