In some respects I agree with what you are saying - the Crusaders game plan wasn't focused on necessarily scoring more tries than the Reds. They were prepared to take whatever points were available - as were the Reds. This has been their approach all season, particularly in the finals, and most people would describe this as 'smart rugby'.
The Reds took far more difficult shots at penalties than DC's shot from the scrum penalty you mention - and they took these shots with a much less reliable kicker than DC. I have no doubt that had Horwill been in the same situation as McCaw, he would have told Quade to have a shot at goal.
The Crusaders definitely weren't able to score tries at will - and I don't think anyone has argued this. The Reds defense was quite good all game and when DC crossed for the Crusaders the Reds line had looked quite good when the Cru had kept ball in hand, and it took a good read and a better kick to score.
Both teams, all season, built their game around defense and counter-attacking opportunities to score. This was evident in the final with the Reds two tries coming off counter-attack and the vast majority of Crusaders missed opportunities coming off counter-attack also. In the final both teams struggled to create attacking opportunities (apart from counter-attack) largely because of the way Bryce refereed the breakdown - both teams were allowed to slow the ball down and get turnover ball. For this reason, in the final ten minutes the Crusaders were really up against the odds and the score-line dictated that they couldn't kick it away to play field position. Nevertheless, they did create opportunities to score in the final ten minutes but execution let them down.
Had their line-out been working properly they would have been playing the game at the right end of the field a lot more often, which is the first and most crucial step in being able to scoring points from penalties, field-goals or creating tries from building sustained pressure with ball-in-hand.