It hasn't been picked up on new exchanges.  Way over 500btc worth has been sold already at this low price.  Miners are selling and buyers are buying.  In addition, because of difficulty vs price it has been profitable to sell at 2-4sat and then buy more mining power.  For example I sold 5mil at 3 sat, and made 9 mil from the hashing power I bought.  Until it hits an exchange that can handle more volume (big spenders don't want to put their money into a 'beta exchange'--with a scary disclaimer) at these prices it will continue to be profitable to dump and reinvest.  As the price rises mining interest will rise, increasing the difficulty.  Its not exactly linear but say it hit 20 sat, then buying mining power and regular mining power will sustain profit at a much higher difficulty.

In the end though, these types of discussion don't support the purpose of this coin.  Use and idea should be the aim of the coin, and that will bring growth.  If people look to the coin and only see how to mine it and its profitability it defeats the idea behind it which is the power behind the idea.  In my opinion when looking up Karmacoin the ways the use it, and idea behind it, should be foremost, and how to mine it and sell it, should be buried within the site/thread/etc.

Obviously, this takes time and resources, and more widespread adoption--which from what I can tell the devs are working on.  Still, anyone with interest in the success should definitely approach the devs with code and ways for it to be adopted.  Also, people aiming at reddit are aiming too far in my opinion.  Getting adoption on a small scale in many places will cause people in charge of larger audiences to raise their eyebrows.  Its a big risk for big money sites to jump on it, but if more and more small competitors take hold, the larger ones will find interest in it.