You can have many copies of your password manager database in many places, but you have only one Google. If you lose one thing, what would you rather lose? If you lose a password database, restore a backup. If you lose access to Google, what then? You can't restore a backup of Google. Stick around HN long enough, and within a week, you'll read stories of people losing access to their Google accounts for unexplained reasons (aside from a robot not liking them).