...If science is the friend of religion, then why is irreligion more common among scientists than among the general population?
		
		
	 
I would argue that religion/theism is the 
majority worldview among scientists.
Of course I accept that you probably want to pick and choose who is allowed to call themself a scientist.
Do you claim that it's hard to find 
millions of Hindu scientists in India?
How many muslim scientists do you think there are in Indonesia?
You think the majority of scientists in China are atheists?