Tongue-in-cheek as this group perhaps is, the title and the motto are nonetheless deeply counter-cultural things to say in an age when approximately 1 out of 5 persons in the United States identify themselves as "spiritual but not religious."
The satirical website Stuff White People Like makes short shrift of that identification:
White people will often say they are “spiritual” but not religious. Which usually means that they will believe any religion that doesn’t involve Jesus.
Popular choices include Buddhism, Hinduism, Kabbalah and, to a lesser extent, Scientology. A few even dip into Islam, but it’s much more rare since you have to give stuff up and actually go to Mosque.
Mostly they are into religion that fits really well into their homes or wardrobe and doesn’t require them to do very much.Ouch!