But are you sure we know ALL of Satoshi's addresses?
If Satoshi was still mining in 2011 like any other 500+ people mining at that time, how would we know?
A total of 2,650,000 coins were mined in 2011. So Satoshi might be having around 5,300 coins from 2011 (considering the median scenario). It will represent just a small fraction of the coins which he mined during 2009, and so we can ignore them. But proof seems to indicate that he gave up mining in 2009 itself.
I always suspected him to have some coins we can't trace back to him. Of course we know about the first blocks that have been mined by him, but what about the blocks that have been mined in the following years? He could very well have mine them in the pool.