Yeah, I've seen quite a few tape drives kicking around in a datacenter that I'm sometimes in, including brand new ones being installed. They are still a pretty good option for storing backups due to the capacity of modern tapes (up to 12tb uncompressed for modern LTO-8 tapes). Performance pretty slow, especially random performance (if you want any sort of random access, forget about tape) but they work out pretty well for long term backups where you would be restoring a large amount of data in one big chunk rather than pulling off individual files.
The tapes tend to work out a fair bit cheaper than hard drives of the same capacity. The drives are generally quite expensive so for small amounts of data you'd probably find hard drives to be cheaper but they can work great for things like offsite/daily backups onto a stack of tapes or, for really large capacity, a tape library can be used to automatically feed tapes into a drive. Compared to using a large RAID array to hold backups, you also get the advantage of lower power consumption (you are just powering the tape drive when you are writing to it instead of having to power an entire RAID array 24/7) and don't have to worry about drives failing in an array - if your tape drive fails, you won't lose the data stored on the tapes and the tapes themselves are incredibly reliable. It's also not a bad idea to have backups stored on a pile of tapes that are completely offline rather than storing them on a backup server connected to the network - it's going to be pretty hard to accidentally (or maliciously) wipe out backups if they are stored on tapes sitting on a shelf in a secure location!
