With regards to this recent question:
I do think there's a disconnect when the question gets -4 and the answer gets +3. It encourages people to answer.
Over on MathOverflow we at times had the idea of turning lemons into lemonade. That is, when the question is too easy, but you feel the urge to answer it, think of something related that is interesting and research level, and put that in an answer. Without just answering homework level questions directly.
Any pros and cons?