I wonder if it's anything like baseball, where you can swear as much as you want, but you can't use any form of the word "you." "You're a thief" would get you tossed much quicker than a long string of tirades. I'm gonna split the difference and say that Serena was out of line and deserved all those penalties, but that if she was a white male star she would have gotten the star treatment on two of them.