You know, if they did ban him, they would be breaking the laws of the game, because there is no law against backheeling the ball into the back of the net. As long as the player only takes one touch in attempting to score from the penalty kick, that's fine. You can't ban or even fine a player of showboating, it's against the rules of football almost. What this is is essentially showboating, it's no worse than chipping the ball in from a penalty, showboating but not illegal.