Why is Reddit so anti-religion?

I saw a post of a guy who got gifted a car and the first thing he did was praise god. In the comments, they were bashing him for "Thanking a sky fairy before the actual people" which I felt was very disrespectful and inappropriate. Another guy said "What a humble man, before anything he thanked god" and he had 24 downvotes. Why does Reddit as a whole think this way? Why are atheists so intolerant? What is wrong with religion?