One point would be that if you're setting up rackmount server hardware, it still tends to come with a CD drive rather than DVD. That's one of Debian's primary purposes nowadays, given that Ubuntu has eaten most of its desktop market-share away.
From whom? Dell doesn't, to my knowledge, offer any CD drives. It's DVD or nothing; we usually choose the latter due to iDRAC's virtual CD/DVD capabilities anyway.
The last few rack-mounted servers we bought came with DVD writers, which seemed a little redundant to me. In our case, we only ever use the DVD drive once, to install CentOS, and then it's closed up and never used again. I can't imagine any situation where you'd want to write a DVD using a server...
I've talked to many an admin writing their backups to dvd. Not the way I'd do it, but..
I haven't seen a rackmount server with a CD drive for many years.