I think anyone in Western society who made antitheism into a religion would choose Satan as the core symbol. And there is certainly a "religion to end all religions" thread in the weaving of what we know as Satanism. I know that for myself, the only religious impulse in my Satanic practice is antitheism. The only rituals I ever do are to blaspheme. I don't seem to need any other catharsis.
Only because they think Theravada Buddhists are all "spiritually finding god though meditation".
My favorite thing of late is to line up the "The Three Universal Truths" with the commonalities of antitheism and Satanism.
Annica - Impermanence. Right there is a religious precept that everything dies. No eternal soul to be reincarnated accordingly. A position that contests the "spirit" of eternal divinity.
Dukkha - Suffering. The position of "Life is sufferring" directly contests fluffy premises of the "symptom of the universe". A love that graces inhabitants with continuous adversity by darwinian design.
Anatta - No Self. THE ABSOLUTE MOST ANTITHEIST OF THEM ALL. Life is only what you can experience with the senses. The nature of our "being" as phenomenal.
While Buddhism does have a "cosmic order", it's actually more in line with the "life force" brought up in another thread, as an illusion within the natural environment that gives an appearance of order because we observe it. (If I interpreted that correctly).
If I did I feel it lines up with antitheism, especially applying the ideas in the Christian West.
I'm also comfortable posting this SAT analogy on the topic:
1. Satanism: Judeo-Christianity
C. Buddhism: Hinduism
Bottom Line : In Western attainment the thing the binds all religious RHP premises is faith. The very definition of abstraction as ideas instead of what can be directly experienced. To be spiritually fulfilled through fanciful thoughts with only faith and confirmation bias in support.
It's as natural for the religious impulse to be antitheism as for the patriotic impulse to be anarchism.