James explicitly stated that extortion is against the CoC:
Also the Code of Conduct itself has a point mentioned by Steggs:
It seems a game specific definition of what griefing or stopping expansion actually is but if you feel your expansion is being hindered, the simple solution is to simply a.) talk to the other player and, should that fail, b.) talk to Steggs.
And as @DonBab just mentioned, this isn’t changing any big mechanics, just makes selling of beacons easier.