Why aren't all CD players also DAC's?

Several years ago I had a California Audio Labs Tercet that was a one-box CD player but to use it as a CD player you installed the small RCA jumper from the coax "audio digital out" to the coax "audio digital in". In other words, the transport and the DAC parts of the machine were separated, so you could use it as either a DAC, transport, or regular CD player. That was prior to when the computer audio thing got big.

So my question is, with everyone nowadays having digital music on their computers and needing a DAC to play it through, why do manufacturers still make single-box CD players with no options for digital inputs? How much extra cost could it possibly add to allow that feature? That would certainly make the unit much more versatile.

Or am I just missing something?

Michael