My personal rule of thumb for magical ethics is not to read half-baked blog posts on ethics.
Instead, I suggest taking a philosophy class on ethics or reading something about different ethics systems. Truthfully, living an ethical life is important to the way I practice witchcraft. My tradition often talks about the Witch as the person who will speak the uncomfortable truth or do the hard task that needs to be done. Essentially, a form of utilitarianism. A Witch's goal is use his or her magic (and hands, feed, head, heart and etc) to leave the world a little better than he or she found it.
I can't say that never means I never act selfishly. Of course I do, I'm a simple human being. But I aspire to making things a bit better than I left. I will still do magic own well-being. But I also try to use that well-being to support my family and friends, my neighbors and community, and the web of life as I know it. It's probably cheezy, but there it is.