I've seen on several occasion that it is not considered wrong to ask a user if he/she could please accept an answer. For instance it is discussed here. My question is slightly though significantly different.
It has happened to me, more than once that I see a (quite interesting) question to which I know the/an answer. Out of curiosity I click on the OP's name to view his/her profile first. I then see that this user rarely accepts any answers, even if they completely solve his/her question. So I would like to know how well received an action like this would be: place a comment that says something like:
"Though I think I can be of assistance to you here, I've noticed that you rarely accept any answers and I therefore choose not to answer your question, because I'd rather help someone that is more likely to express his/her appreciation."
Edit: My idea was that comments like this could encourage a user to change his/her accepting habbits. I've read in one of the links by Gerry Myerson that accept marks are not a significant issue. I agree with that as far as you consider the mechanics of the site or the wellbeing of someone who answers (no one will die if their answer isn't accepted). But for me it's more like a common courtesy thing. If I know someone is not going to bother to show his/her gratitude, I just don't feel like answering. Anyway, that just my way of looking at it. I was just curious how other feel about this.