Making things is inherently satisfying. People feel good about themselves when their efforts are not futile and meaningless.
This really is pretty universal as the creative impulse can be found in just about every instance of human beings that's been recorded (or is known to me anyway.) Whenever it is lacking in people's lives, they tend to be pretty unsatisfied.
Forgive me if I sound like the Unabomber, but a good example of this is the misery that people feel as a result of dehumanizing industrial jobs. Because people don't feel that their time is spent in a way that allows them to make a mark on the world, they are frustrated and pissed.
Contrast this to the satisfaction gained from building or repairing things with your own two hands and you'll understand what I'm talking about. Computer programmers know what I mean; it's fun to write code because you turn an inert pile of itty bitty wires into something that does something cool; you turn it into something cooler.
So grow your own, brew your own, build your own. It's fun, and makes you independant of exploitive economic systems.