The allure of carbon fiber in industry has to do with the properties of the material that can be produced. Home made carbon fiber won't be all that great of a material compared to what people see out in the world (on race cars, planes, etc...). Production lines for producing commercial carbon fiber is super expensive ($100 million+). Zoltek has a basic rundown of the process [0].
[0] http://www.zoltek.com/carbonfiber/how-is-it-made/