Cost effective cds are in quantities of 1000. Cost effective booklets/tray cards are minimally 2500. Most issues deleted sell below 200 a year. You do the math. None of this takes into consideration the expense of warehousing, etc.
That's cost effective, I assume, at the normal price of a CD release. I'm thinking on-demand CDs would be able to get a higher price because they're on demand and therefore purchasers would have considerably higher motivation. Warehousing, obviously, would not be a factor since they wouldn't be warehoused, they'd be printed on demand and shipped at once.
BWTFDIK?
Read carefully and you will see I was responding to "proper CDs", not CD-Rs.