OK, I have to confess to being a big defender of defensive sport (and not just football). That much has been pretty obvious here, so I have a bias here. That said, I will still say that the Holland-Czech match has been my favorite in years -- even if quality defense was about the only element lacking from it.
But if you want goal-scoring machines for entertainment, we've got basketball for that. There's so much scoring, in fact, that the act of scoring has been rendered almost meaningless.
If Greece needs to resort to the grind-them-down, Germanic, defensive style of play, that's fine by me. They're not Brazilians, and they're never going to be. Their opposition has to go into matches knowing that. And if they cannot beat them at that level, then Greece is doing everything within the fair laws of the game to best ensure a victory.
It may not be pretty, and it may not produce a lot of commercial endorsements in the process. But if it's effective and it's legal -- more power to them. Let someone else try to topple them if they think what they do is so simple.