I'm pretty sure there are different groups also among the same exact religion. If we asked to a large group of Christians whether we, say, should help immigrants, we would probably end up with 3 types of answers: "yes, let's help them!" - "yes, but only for very basic needs, then let's kick them out" - "nope, let's build a wall and let them rot on the other side".
Of course the 2nd and especially the 3rd group have absolutely nothing to do with anything christian, and they profess them as such only to not feel guilty, or possibly because the society they live in requires that (how many votes would a politician get is he/she admitted being atheist?) - religion for them is just a series of acts (go to church, make offers, say prayers aloud, etc.) intended to cheat the system and appear as good people while in realty they aren't.
I am also sure that the 1st group live a better life, which doesn't mean they'll earn more, actually it's quite likely the opposite, but they grow better "antibodies" to overcome difficulties without anger.
BTW, I'm writing this as a complete atheist. Spending most of my youth in catholic schools helped me to know many people of all those groups, and believe me, for us atheists recognizing someone that is just pretending to be religious is truly easy.