1. d4 Nf6 2. Nf3 g6
1. d4 d5 2. Nf3 g6
1. d4 Nf6 2. Nf3 d5 3. e3 g6 (the so-called "Sneaky Grunfeld")
Basically, the Zuke is designed to attack black's castled king under the assumption that the bishop will come out to e7 or d6. If black plays g6 and Bg7 instead, then the setup isn't right for that. But there are other lines white can play instead.
i agree that white have good lines against those while playing the zukertort:). 1.d4 Nf6 2.Nf3 g6 and 1.d4 d5 2.Nf3 g6 can be met by the barry attack or 150 attack. the sneaky grunfeld is a little trickier but white still have a good game with something like this
I'm not worried about which opening is the "flavor of the month" with GM's. At that level, though opening theory may be important, ultimately, it's knowing how to analyze a position, having a plan, a keen tactical eye, and good end-game technique that brings home the point.