Professional sports league like the NBA and NFL believes that betting on sport games will threaten the integrity of the game because athletes would start fixing games. This is what we call the "slippery slope" fallacy. "If we did this, then this will surely happen."
There are no facts or figures that would support this argument. In California, we have numerous casinos and horse tracks that can benefit from the revenue that sports betting can generate, but we are stuck in a silly law that is devoiding us of needed revenue. Meanwhile, Nevada is the exception and continues to monopolize the industry.
California needs this and we should not be be held back by assumptions that have no merits.