this is another interesting thread and I too enjoy hearing everyone's (differing) opinions as it helps me to examine my own thoughts and actions on the matter in question.
Is it ethical to read about another person's situation that has not asked you to read about it, and/or does not know that you are doing so?
I have to go back to the original question, which I have seen many times in this forum over the years. The thing that always sticks out for me though is not the issue of ethics because I am confident in myself that I am an ethical person, but the issue of reading about someone without their permission...no matter how you cut it (in my view) this is
exactly what tarot is! a tool to peer into a situation from differing perspectives/directions and hopefully gleen a better understanding of it and the people involved.
Even when I read
for myself I am still reading about other people (gasp, without their permission/knowledge) because their lives are connected to my life and what they do or don't do, think or don't think, can affect me (whatever issue I am reading about for myself). When we read at the request of others, we are still reading about people and situations affecting them that have not given their "permission" to be read about. So, my point being, it is not so cut and dried an issue. And if I felt it was "unethical" to catch a glimpse into someone else's inner life (as though I was driving past their home and their windows were open and I could see in), then I really should not be picking up the tarot cards at all because it will happen (if I have my eyes/heart open), that is the nature of the cards themselves.
I agree with those that have said "it depends" because I don't make it a practice to peer at the dirty laundry of others just for kicks and giggles, but if I wish to know if I can help someone or I wish to know what's going on with someone or a group then I will read about that situation and obviously I'm not going to call them up and say hey, I think you need a tarot reading because
I want to have a better insight into what's happening with you!
Personally, I think the "ethical" part comes into play with how we utilize whatever information we gain (whether this is a reading done with or without 'permission')...
when I read for someone by request I try to present my take on the cards as gently and as straight forward as possible, and with the understanding that nothing is "set in stone" and that the reading is only as good as my personal intuition and understanding of the cards. which is to say, I could very well have it all wrong. even then, I have a few times in life had people just become completely irate with me and argue every point I tried to show them in the cards. so be it, I did my best and I was ethical.
when I read for someone as a part of my own understanding of the world and the people around me, whatever I "see" in the cards never leaves that reading other than to possibly help me interact better with the person or event in question. In other words, if I were to read in this manner and I
thought I saw in the cards the divorce of another person I would not be pounding on that person's door saying 'OMG, you're going to get divorced!!!'. First of all, that would be stupid IMNSHO, but it would also be unethical because I don't
know that for a fact and all I would be doing at that point is fearmongering and perhaps creating a self-fulfilling prophecy by putting doubt into that person. It also doesn't mean it's not going to happen, but unless this person asked (beforehand) specifically to know what the cards had to say, then it's not my place to try to force that information on them.
I hope my 2 cents has made some sense