This is more common than you might expect. Another example: The electronics and games section at Target is staffed and run by a company called Marketsource.
Well, there's one comic that is his motivations for building the app, which while admirable, but I'm not sure if appealing to my pathos makes me want to use the app any more than I would have otherwise. The other comic is better directed at why I/you might want to use it.
I reference this one a lot, http://www.music.mcgill.ca/~ich/classes/dafx_book.pdf, and have enjoyed it. I get lost in some of the math, but it's very thorough and practical. It was also personally reccommended by the guys at Goodhertz, and they seem to know what they're doing.
Hell, at my last gig, we used AppleScript to build custom DMGs. No doubt there are probably easier ways to go about it, but we didn't need a GUI and the end result was consistent.