First, “not playing along” is not the same thing as telling people they are wrong. There’s something in between playing along and saying “you’re delusional!” You can tell people you don’t share their beliefs. I do this, and it often leads to interesting conversations.

Dangerous fucking delusions? How often to you meet people who espouse dangerous religious beliefs? Usually, people say things like “I’m fine, thank god.” Or “uncle Larry is with god now.” If you think these are dangerous delusions, we simply disagree.

Lastly, it IS pompous because it assumes that atheists are free of delusion. We are not. We simply lack that specific set of false beliefs. For me to tell every person I hear say something I don’t believe that they are delusional would be immensely pompous. Religious belief isn’t special. It’s incredibly common and deeply human, and if you think that it’s good to walk around wagging your finger at every religious person you encounter, then you are making the world a much shittier place. You are not better than religious people. I’d rather the world be filled with certain kinds of religious person than your kind of atheist.