Lots of stories about having google account connected to adwords locked out for various reasons, not all valid.
There's are several third party Google backup services for the paranoid...
It's not about backups - it's about loss of ongoing use infrastructure
The backup mitigates the problem because, if you are banned, which only happens to fools and fakes, you can take the backup and set it up on another service. Sure, you lose a couple of days of time migrating, but that's not a reason to avoid choosing a better solution.