To understand these beliefs, you must understand how people learn what is right and what is wrong. Usually people learn what is right and wrong from their parents. They are told not to steal and not to do drugs. Parents do not consider talking to their children about these things, because they never thought their children could do these things. This leaves morality to be learned on the streets, or in this case, cyberspace.
Hackers learn morality from other hackers, who learn it from other hackers.
A morality of this type only perpetuates the morals that best suit the participants. While traditional hackers would frown upon these opinions, they will not take actions against anyone performing malicious actions. This implies that hackers are not self policing, which harms the image of the majority of hackers and has created an outcry from the general public that something must be done to crackdown on all hackers. It is extremely difficult to distinguish a well meaning hacker from a malicious one. Unfortunately, they both present a danger to any computer system.