the bitcoin system is based on trickle down economics (the rich get the riches and it trickles down to the poor), yet a large amount of miners hoard their coins!
The same is true about the real world economy. A VERY small minority hold most of the money that there is.
for an economic system to work, there has to be actual economic activity going on.
One of the biggest reasons that bitcoin hasn't caught on is because the system is not readily accessible to the average person. Having to set up multiple accounts just to safely transfer normal money into bitcoins is not very straightforward because there is no official documentation, and the same goes for managing the default wallet program, which really does not have a very user friendly interface. There are sites that accept bitcoin see here:
https://en.bitcoin.it/wiki/Trade, and people do trade items and services on the bitcoin forum here:
http://forum.bitcoin.org/index.php?board=5.0. The obvious flaw that can be seen here is that the majority of all bitcoin transactions are between people who have some idea of what they are doing/have faith in the concept.