you also have to look at the good sellers thread and see that the transactions are vague. Most of the just say "Add <namehere> as good trader" and there is no mention of for what or why. So expecting someone to go through that and add to scores is not really doable.
I went through it and tried to give credit to anyone I dealt with. Unfortunately there were names that I couldn't remember what it was I bought from them or sold them so I couldn't fairly leave feedback for them, even though I know they were a good trader. There were others who were not current active members, but I still left feedback if I remembered what it was, just in case they ever come back.
This doesn't mean that I expect them to remember and give me feedback based on the fact that they got it. I would rather them remember what it was for so that way the feedback is more honest.
The only problem with feedback systems is the fact that sellers will be so demanding about getting feedback "for their reputation", that they will turn to not trusting their customers, and that they will hold the customers feedback hostage, until they receive good feedback. Just like what sellers do at e-bay.
The purpose of the feedback lets everyone know who is honest and great to deal with. It isn't something that is to be expected during a transaction, but something done out of courtesy.