And what in law says that players have a right to appeal against decisions? In fact law says completely the opposite ...I would strongly disagree with cautioning the first. What that would achieve is banning any appeals against decisions.
The decisions of the referee regarding facts connected with play, including whether or not a goal is scored and the result of the match, are final. The decisions of the referee, and all other match officials, must always be respected
Obviously there will always be some appealing, even though it is pointless as how often do referees change their decisions, but saying "are you sure ref" is a lot different to racing towards him and / or crowding him.