Former NBA referee Tim Donaghy was interviewed on ESPN awhile back. He was out of the NBA after having been found to have violated rules against betting.
The interviewer went over the predictable ground, bringing out Danaghy's assertion that he was able to win 70-80% of his bets simply by knowing which referees were pissed off at which players. The logical next question was "were games fixed?". Donaghy insisted no games were ever fixed, because no calls were made that were not "justifiable".
The fact that he could make this assertion with a straight face, and that an aggressive interviewer was not able to challenge it, illustrates a huge problem with pro basketball. What it means is that the calls are so subjective many could go either way, in which case it is all the more important to have totally neutral refs. But the refs are human and apparently none are totally neutral.
Then the interviewer asked the great question, "Do you think the NBA is more of a sport or more of a show"? The answer was more of a show, which upon reflection seems 100% true. If so it explains a lot about why the NBA has never caught on as a major spectator sport like baseball, football, even auto racing. The public seems to have an innate sense that what it is watching is pure show. The NBA feeds into this uneasy feeling with its stupid dunking contests, which have nothing to do with basketball skills, and everything to do with showmanship.
Of course to keep what popularity it has the NBA, like the rigged quiz shows of the1950's, has to maintain the illusion that it is really an honest contest. When the word got out that the quiz shows were rigged, they all disappeared from the air. So would the NBA disappear if the truth became known.
What about other sports? Haven't you been curious about why the camera always seems to find the holding violation after the ref calls it in pro football? Don't the refs ever get one wrong? I think the answer is that there is holding on virtually every play, and only occasionally do the refs actually call it. Consequently, when they do call it it is easily found by the camera. Again, we have a situation of great subjectivity, which makes for a bad situation if you are going to consider this a true sport, a true test of skill. It is easy to imagine a ref who is upset with a particular player who he doesn't like, and watches that player extra closely for violations.
A recent court case illustrates the basic point here. The NFL had contracted with a particular company to exclusively advertise that product. A competitor of the company sued the NFL under an antitrust theory. The NFL's response was that it was a single entity with the teams being 32 separate components of that single entity. Hence no antitrust violation. The NFL won the case on that theory. If this doesn't illustrate the reality, I don't know what does.
Another example is the group of fans who complained about a team not playing its best players in a recent meaningless end-of-the-season game. The fans wanted a show, they didn't want the team to get ready for the playoffs as the situation clearly called for. Such an outcry would be unheard of in a real sport like baseball, tennis, golf, etc.