I think that most players that do this had it happen to them when they were lower lvls. I know when I was below 40 I got ganked all the time. (now lvl 60 fury warrior) Even if there was an honor system, I think some people would still do it just for the satisfaction of inflicting the same kind of "punishment" on low lvls as they recieved. I have never camped because I have set goals for my-self and none of them can be achieved by camping or just walking around killing lower levels. Even when I pass an alliance by (i'm horde) I wont mess with them unless they are attacking other horde. Just my thoughs.