[natural219]

I would go even further and say that this model is a special case of the more general advertising/marketing model of "Give Valuable Stuff Away For Free". As an example at a smaller scale, content marketing (in terms of blog posts, videos, pdfs, and other informational content [1]) is a great way for businesses to get eyeballs on their page and establish themselves as authority in a particular subject.

This even works on an individual level. I would say that contributing to open-source development on Github is a great way for individual developers to "Give Away Valuable Stuff" and in term become more visible and attractive to respected software businesses who may want to hire them (as full-time employees or freelancers).

[1] Brendan Dunn and Eric Davis have a great podcast about this which provides an excellent definition of content marketing: http://brennandunn.com/episode-006-the-sales-pipeline/