Well, every and all magick system has rules. Even the Dark arts have rules of their own. Just because they are practicing "Black" Magick doesn't mean they have rules of their own. Based on my experience every magical system has equal amounts of ethics within them. It just depends on the attitude of the practitioner towards the system he is using.
For example A satanist might disobey any or all rules given to them by anybody or even their superiors. They think that their way doesn't have rules but little did that satanist know that there are many ethics in satanism and many rules and self-development, It is a psychological problem.
Im not pagan or wiccan. but i have the limits on what magic i use. I dont use black magic because I believe in the threefold rule. Also I dont want to use too much magic, like with a family problem i ended up having to fix with magic, i tried in vain for a few weeks. :P You dont have to be pagan or wiccan or whatever to use magic. just follow the rules you wish to set for urself :P if u wish to follow a religions rule, thats your choice.