I think the line is that "working the refs" so that you might get some calls in the future is fine. But anything other than that is not constructive.
The guy that best exemplifies constructive complaining about officiating is Phil Jackson. He picks the one call he wants to get in a series and publically challenges officials before the series starts. Last week he complained that Kevin Durant was getting undue "star calls". Next thing you know, Ron Artest is getting away with murder guarding KD.
The rest of us blur the line between working the refs and whining. But the closer you are to Phil Jackson complaining, and the farther you are from fans whining about injustices in days of yore, the less of a loser you are in my opinion.