Perhaps we're referring to different organizations here, but I've reviewed Mozilla's mission statement and efforts and it doesn't appear their task has any connection to preventing "Google Earth", as you describe it.
Feel free to replace "Google Earth" with some situation you think is contrary to Mozilla's mission. The exact same argument still applies.
On the other hand, imagine you have two choices. You can either lie, or Google Chrome achieves 90% market share, all of web runs on Pepper, and there is no more open web. (Let's call this world "Google Earth".) Mozilla's mission is to prevent such world, right? Do you seriously think not lying is the right thing to do in this case?
Now imagine you have choices of lying and making Google Earth 10% more likely.
Now imagine you have choices of lying and making Google Earth 1% more likely.
How much Google Earth worth is not lying? Eich probably believed him being CEO is worth some reduction in probability of Google Earth. I would be surprised "not lying" has more utility than such probability reduction. I conclude he didn't decide not to lie because of utilitarian calculation.