I produce my own DVDs for sale on the 'net, which involves:

1. Creating the original video tracks to HD standard & stereo sound
2. Burning the original, and copying from this master, in both NTSC (US) and PAL (Europe) formats
3. Designing and printing the CD/DVD sticky labels
4. Designing and printing the case insert
5. Assembling the final product

That's a summary of my time. The costs, apart from my time, include:

6. Cost of slip cases
7. Cost of label materials (paper & CD/DVD stickies)
8. Cost of ink
9. Cost of DVD blanks
10. Cost of CD/DVD packaging for the post
11. Cost of postage -airmail for non-UK, 1st-class for UK

I also provide, where appropriate, free downloadable tab/chord/SN sheets from my website, to match some of the DVD pieces. The DVDs sell, through PayPal, for £6 in the UK and $12 (which currently works out at around £7) in North America. I've never worked out the profit because the DVDs are sold to those who want a better quality of my demonstration & educational pieces on YouTube. My guess is that it's around £0 per item! (But that's my choice, as the aim of my YT stuff is free educational).

However, it does support the strength of Tom's argument. There's no such thing as "dead" time for a professional, working musician.