I'll bet I can think of a lot of quotes from prominent atheists, printed on little pieces of paper handed out by FAs, that would get religious passengers rather bent out of shape -- particularly when the message is distributed to adults and children alike. And I suspect they would not just "duly ignore" those little pieces of paper. They would complain about them, rightly stating that it is not the proper place of an airline to challenge the religious beliefs of its passengers by distributing such in-flight messages.