To add to your point, which I'm sure is in reference to macro-level phenomenon such as the interdependence of species, symbiosis, ecosystem complexity and the like, it's important to note that multi-cellular organisms are the epitome of individuals (cells) working for the greater good rather than local self-interest. Eons ago single cells started working together and specializing. White blood cells, neural cells and muscle cells don't compete against each other, much less is there white blood cell on white blood cell competition. When cells behavior breaks from the greater good, we call it cancer.
A perfect example of pure self interest is the virus.
Interesting that many people do consider capitalism akin to cancer, or that it behaves virally.
But whereas altruistic solutions to problems require continual interest from the donor class (which is subject the same fads as the rest of our culture), or government coercion (which eventually gets co-opted by political considerations), market solutions are robust because people are profiting from them. We'd all love to feed the starving people of the world, but sending ships full of free food isn't the solution (and can actually be harmful). It's much much more effective to set in motion the market forces that will create a stable food supply year after year.
The Internet is a basic utility and public good. Monopoly usually doesn't seem to be a good model for these kinds of systems.
Without that regulation, multicellular organisms wouldn't exist.
Also, altruism is perfectly at home with modern evolutionary theory because it assumes a more enlightened, rather than simple minded, understanding of altruism.