To stand out from the players
In American sports, the referees usually wear black and white striped shirts. In the NBA, the officials wear grey shirts.
The numbers on cricket shirts refers to player numbers. This is similar to the jersey numbers assigned to the tee shirts of football players. It is used to identify the player who is wearing the tee shirt.
The reason referees wear white and black striped shirts was at first to distinguish themselves from the participating teams. Although other uniforms are becoming more popular.
It is belongs to the player. It is about his rank.
They are the referees vs the linesmen.
They wear numbers for the same reasons that players do. So they can be identified.
It represents to which the number they got drafted.
because you are mean
The NBA refs do have numbers on the shirts for identification purposes so that all the calls that they make can be documented.