Board Thread:Questions and Answers/@comment-5157293-20130324003807/@comment-1713281-20130325222235

^ What he said.

And if nothing else, all coincidences and plot holes in the stories and interconnections of the pantheons can be chalked up to a dues ex machina of the writing staff. Why did all the pantheons find Earth, and not Mars? Because Earth is where the writers chose to set the story. It's not the most romantic of explanations, but it's a tried-n-true fallback reasoning.