Not the section to ask this, but yes you can be banned for buying rsgp, but as a buyer you only get a 2 week ban if caught on your first offence according to Jagex.
this is realllly old.. but i was searchign something and this popped up.. but if anybody sees this please read
i was told by a friend that jagex wont ban you for buying gp because when u buy gp you still play the game more and etc.. but if you sell gp that means ur trying to quit playing and they will ban u for that