At the time, CD writers were not a common thing. Supposedly, CD-RW that could be rewritten debuted in 1997. AOL wouldn't have been giving those out. You paid a premium for them compared to the write-once CD-R, which is what most people I knew who burned CDs at home were using. AOL just sent mass-pressed CD-ROMs.

It would be interesting to know how much waste their CD mailing campaign produced. I think it would be a nice gesture to recognize their accomplishment with a monument: the Steve Case Memorial Landfill.

I always loved getting free writable floppies in the mail from them! Their service was useless to me, but the floppies sure weren't. Then they switched to CDs, which went directly from mailbox to trash, and I was very sad.