What exactly are they dreaming about? I've only dealt with a few, but the open-source hardware companies I've purchased from are catering to individuals who don't need a PC motherboard or a 3GHz processor for their project. Think Arduino or GPS breakout board.
In reality, cost barriers to open source hardware are progressing quite nicely. Access to fab resources in China and pick and place machines are dropping in price; doing it on your own is much more accessible. For examples, check out the aforementioned Arduino or the stuff Makerbot creates. 3d printers at a price-point of $1,000 were a pie in the sky dream 10 years ago.
And lastly, open source isn't always about free as in bear. People still pay for Linux. I still pay for open source hobbyist hardware. I purchase it instead of other roughly equivalent devices because it's more easily modifiable, is easily hacked upon, is often quite well documented, and it's easy to find support.
Adafruit has recently mentioned that "[t]here are 13 million-dollar open-source hardware companies". It seems to be working for some of us.