If you ever watch the science fiction series "Battlestar Galatica" the new version, they have a universe where there is religion, but no Christ or Christianity.
They do a good job of it, but humans have always had some sort of religion, so I've never seen any sort of alternate universe or earth parallel fiction where there was total elimination of spiritual or religious thought unless the future represented is a repressive, dark and dystopian one.
It's interesting that the only way you can completely eliminate religion or spiritually oriented discussion, belief or philosophy among humans is by some sort of totalitarian repression.
It's just one of those things that you have to allow in a free society, no matter how much it might grind your gears individually. It's called tolerance. I don't think a society has to tolerate violence or crime, or dangerous propaganda in the name or religion, though. That's crossing a line where tolerance doesn't apply any more, criminals give up their right to be tolerated by violating certain generally accepted social rules.