I think, when you look at all th factors on all three sides (analog/analog, analog/digital, digital/digital) that you'll notice that each has its benefits.
100% analog will probably give you the best results in terms of resolution and tonal quality/continuity. And working in the wet darkroom is just so fulfilling. To get a decent 16x20, you're spending maybe $300 for a used enlarger, chemicals and $500 for a 645 or 6x6 or 6x7 SLR. $800 and you're rolling.
analog to digital gives you the control of digital, the hitrate, and the analog medium when you want it. It gives you the ability to have 50MP or more out of a negative. You are capable of getting better results than with a 100% digital process in terms of quality, so long as you have the tools to do it properly. To get a decent 16x20, you're spending $500 on the camera, $1500 on the scanner, and $1300 on the printer. $3300 and you're rolling.
digital/digital gives you complete control over everything except how the image looks in terms of "grain" structure. Digital is digital in that sense. This is the lowest cost option if you are willing to stick to the same body for a few years. If you're a 35mm shooter, the Canon 5D, Nikon D200, or Nikon D2X are pretty decent performers. This is the business-photographer's way. The client doesn't care if you're shooting film. The product is all that matters (and they aren't very sensitive to the qualities of the product at less than 30 inches viewing distance), and they're probably going to be happy with their wedding portrait off the D2x. To get a decent 16x20 from this, you're going to have to spend . . . .$15000 on the camera (or more), and $1300 on the printer. $20000 gets you rolling.
So, you see, quality costs more as you go from 100% analog to 100% digital, but your costs per unit out output drop as activity increases. As you fall back from 16x20 to 11x14 and 5x7 print sizes, this relationship breaks down according to the quality of the media and the skills of the printer.
and the x-factor, if you're a high volume pro, is post processing. How much do you save on this service if you're shooting digital? If you used to pay $10000 per month on film processing, you aren't doing that anymore. But, maybe you've hired a staff of Photoshop technicians. . . .
I think it's that digital = increased overhead and analog = increased unit cost. But if you look at a 4x6 or 5x7 print . . . that equation isn't applicable.