Sports betting is huge in the USA. Approximately $4.2 billion were betted during the last Super Bowl. However, American Gaming Association stated that $4.1 billion of those bets were placed illegal. New Jersey and many other states want to make sports betting legal, in which case the government will profit as well.
New Jersey want to legalize sports betting for a long time, but this would be a violation of the Professional and Amatuer Sports Protection Act (PASPA). According to NCAA it would also be unfair to other states. The only state where sports betting is permitted is Nevada.
Many other states like New Jersey want sports betting to be legal. NBA Commissioner Adam Silver said it should've been made legal a long time ago. With the money the government can make with sports betting and gambling, it's strange the congress didn't legalize it yet. However, it can take a long time before the Congress passes a new law that can counter-attack PAPSA and make sports betting legal.