To give you an idea of how open source software works and the forces at play, without getting into specifics I will tell you the history of a project of mine.

Like all lazy programmers, I didn't just decide to write code. Instead I was led there because I was using some software and it didn't do things the way I wanted them done. I got involved in the mailing list and explained what I wanted to do, offering my services to do it. Nobody else was keen on doing things the way I wanted them done, so I decided not to argue and to set up a competing project. Eventually, my project had all the functionality of the first one and worked better (in my estimation).

While I was working on my project, another project started up. They liked what I was doing, but wanted to work on a more portable platform. I wasn't interested in doing a rewrite, but wished them well. Eventually, their project had all the functionality that my project had. They also had more programmers on their project because their project was more popular (being more portable). I shut down my project and recommended that people using my code move to the new project.

The original project that I proposed changes to still exists, but almost everyone has moved to the newest system. I suspect that the person running the original project only keeps it going because he likes to tinker with it and it does everything that he needs. Everyone is happy and we have a much better ecosystem because new ideas could be tried without having to convince the old guard. I would argue strongly that the friendly competition that existed between our projects -- using the best ideas and ignoring the bad ones -- greatly enhanced the exploration of the problem space.

I would likewise argue that if we had all pitched in on the original project that we would never have gotten such a good system in the end. This situation is far from uncommon. You see it in virtually every open source project around. It is one of the best things about it.

The responses here are rather depressing. As a(n extremely humble) coder, to have a half dozen posts complaining of fragmentation is rather depressing. Somewhere there must be a non-trivial program which was written purely for the sake of doing so, but for the general case we may say that software is written neither accidentally nor arbitrarily, but to remedy a lack in existing software. It is in exceedingly bad taste to complain about any article offered gratis, but to say that the work involved was counterproductive is quite offensive. As a remark applied to a large and popular software project, as more than one of my fellow commentors have, it is a slur against the entire profession. The software is gratis even to ingrates, but -- as a programmer, you should consider the beam in thine eye. And if there is someone who instructs a computer but will not lay claim to being a programmer, well...perhaps silence is better than 'removing all doubt.'

Touching more directly on the subject at hand, the question which most interested me was the one on exploitation. My opinion is that F/LOSS is indeed exploitative, especially if you aren't paid for working on it. Closed source may be just as exploitative, with the added sting that you may not be compensated commesurably with the commercial exploitation of your work. However, with the understanding that the fruits of your labors are often not directly monetizable, the value of the F/LOSS network may be presumed to be proportional to the number of participants, and reaping the benefits of this is limited only by your ability to consume them. That in itself may not generally be exchanged for a cup of coffee, but for many people it is worth an excellent salary, and ends up being a good value proposition. Discounting the ecosystem, "self-exploitative" isn't a bad description of contributing to F/LOSS projects, and many other walks of life besides. Taken on the whole though, it's abundantly clear that an open development model is highly beneficial to both its participants and users.