It's no wonder that capturing on c4 immediately is the most popular move, but there's nothing terribly wrong with the optimistic and thematic h-pawn advance.
1. g1f3  1... d7d5  2. g2g3  2... g8f6  3. f1g2  3... g7g6  4. c2c4  4... d5c4  5. d1a4  5... f6d7 