Nightly backups still mean you can lose up to ~24 hours of data.
This is in stark contrast to, for example, AWS S3. From the FAQ [0]:
> Amazon S3 [is] designed to provide 99.999999999% durability of objects over a given year. This durability level corresponds to an average annual expected loss of 0.000000001% of objects. For example, if you store 10,000,000 objects with Amazon S3, you can on average expect to incur a loss of a single object once every 10,000 years.
> Amazon S3 ... storage classes redundantly store your objects on multiple devices across a minimum of three Availability Zones (AZs) in an Amazon S3 Region before returning SUCCESS.
In AWS parlance, an AZ is a physical data center, and they're built far enough apart so a fire, flood or tornado will not affect all of them.
There's a reason S3 (and similar) cost so much more than "hard drive attached to a server" storage. If you don't need the durability than of course it is overpriced -- but on the other hand, if you try to provide that level of durability yourself you'll quickly see it's a bargain.
[0] https://aws.amazon.com/s3/faqs/#Durability_.26_Data_Protecti...
