Patent examiners don't have discretion. The special patent court (CAFC) is filled with patent lawyers that decide cases based on their own personal interest in a more expansive patent system. Except where the Supreme Court reviews their cases, they have total power to set precedents and those precedents always favor trolls over creators and innovators.
http://arstechnica.com/tech-policy/2012/09/how-a-rogue-appea...