On a good day, I think Anon is kind of like an allegory for the duality of human nature they clearly have some members who are capable of doing good; but even the most altruistic person has their limits. Just, as an example, one of my good friends works as a foster for the local animal shelter; she also happens to be in law enforcement. At one point in time she was hoping to be an officer like one of the ones in the various Animal Cops series on Animal Planet, but acknowledged "On a good day, I'd arrest someone and save an animal; but eventually I'd reach my breaking point and find it really hard not to shoot a suspect in the face."
Maybe some of the people in 4chan are capable of doing something like that; and I honestly can't say that I wouldn't act in a similar manner; especially regarding some issues I'm very sensitive to (abuse and bullying come to mind). I just happen to think its incredibly fascinating that their group dynamic has manifested itself in the manner it has. On one hand they appear to be sort of cyber Robin Hoods; and on the other hand they appear to just be hoodlums.