The only thing i can see against the hide function is basically as Vikings & rod say, but not so much in the case of Kights & Rooks as they could be playing alot more games.
What about a pawn with a max of 20 games AND alot of there opponents decided to use this hide feature. They would look at opponents on-line and just go again as there would be no reason for them to stay (apart from hope lol).