cstheory.SE has a great version of this:
You should only post questions you're actually seriously thinking about. Users are expected to do their part and try to answer their question by themselves before posting them on cstheory and asking for help from others. Search to see if your question is already answered somewhere else (e.g. Wikipedia) before asking a question. Try to make your question interesting for others by providing some background knowledge. Remember, questions should be based on knowledge sharing, not on shirking. Shirking goes against the spirit of the site.
I think something like this should be in place and enforced. A lot users are treating this site like an extended bitcoin FAQ, asking questions (like Is Bitcoin a scam? for instance) that they THINK SOMEONE MIGHT WANT TO PROBABLY ASK, but already know the answer to themselves or don't personally care about the answer to. If this question really is going to be important to someone, just wait for that someone to ask it. It is important to seed the site with good, technical, and high-level questions to set the tone; instead of asking obvious FAQish questions.