You shouldn't treat Dropbox as a backup service, there is a reason 1Password creates a folder called "Backups" in the user's Library folder (or the Documents folder if you're on Windows), even if Dropbox sync is enabled....unless you decide to add Windows or Android to your collection of devices, I guess, or enjoy the possibilities of making a manual backup that we have now with Dropbox.
That's because Dropbox is a sync service and not a backup service. Google "syncing is not backup" for more info