I asked a question that went for a long time without getting a definite answer. Later, when I looked at my user page, I saw the text "Have you considered accepting an answer or starting a bounty for this question?". I tried to figure out how to start a bounty, and read through the FAQs, and eventually found out that I can't offer a bounty unless I have at least 100 reputation points. So my suggestion is to not suggest starting a bounty to users who are unable to do so.