The refs definitely protect the stars. But the stars are why people pay money and buy tickets. So there is definitely pressure to keep the stars off the bench a

The refs definitely protect the stars. But the stars are why people pay money and buy tickets. So there is definitely pressure to keep the stars off the bench and on the court. And if one team is extending a lead, they seem to love to call fouls to keep the score close and the game interesting. Whether they do it consciously or unconsciously or at the behest of the nba, who knows. But definitely the NBA, like all major sports, are more entertainment rather than sport.