naturalism

There are many branches of philosophy, within which an entire web focuses on how we humans think and feel about the natural
When it comes to the atheistic worldview, logic, rationality, empirical demonstration or just simple philosophical argumentation, being an atheist provides very little cognitive dissonance in comparison to theism.
Needless to say, my experience of camp was nothing like Moonrise Kingdom. So where does this distinctive tradition come from and why, historically, do we not practised it in the UK?