In most matches played, there is nothing inherently wrong with getting out of your chair to check a shot or position, as it is a check and balance to keep a player honest and in some cases see if there is potential for a foul, in which case the TD or an impartial party is called over to watch the hit / shot.
In a match with a referee, there is NO reason whatsoever for the player not at the table to get out of their chair. The referee is watching each of the shots, and will make the call regardless of whether or not the opposing player looked at it or not. In a tournament like this, getting out of your chair when it is not your turn at the table is poor sportsmanship.