Resurrecting an old thread here. But my wife's Moto X has the exact same problem. Mine does not. I've reloaded her phone and the problem returned.
In fact, I just switched her out to a second gen Moto X and the problem followed her. I'm convinced it has to be something with her Gmail/Google profile, but I have no idea where to look.
Just like the OP, can't find any settings on the phone itself that would change this. Any other ideas?