I'm not atheist but I am Wiccan, and to make the presumption that everyone believes in a christian "god" would indeed be a bad assumption on Pepsis part.

If they alienate a group or rather several groups all at once then their sales would dive into the toilet so this is how they solved the problem.

Smart move for Pepsi and their marketing team.....stupid move to try and boycott it for the narrow minded view that everyone believes in the same view of god as they do.