You seriously do not understand the ecosystem. Many of the major projects have core teams which are FTEs of the company, and others donate funds for outside contractors that are key contributors. Far from being paid nothing, I've known several that began as unpaid contributors and eventually went direct, started their own companies to service their piece, or received federal grants ( from the US Army for instance ). Other projects start on a purely unpaid volunteer effort, become essential and evolve into well funded projects. Firefox was originally a commercial product, then donated as open source, and now has spun off some of it's projects. IBM, Google, and others have transferred many internal projects into the open domain. Far from exploitation, FOSS is almost hyper-capitalistic, in that it short circuits the rent taking inherent in closed source monopolies, it allows microscopic participants into markets alongside the giants.