Kalos is said to have some sort of a connection to the Kanto region, so maybe that's got something to do with it?
Anyway, this isn't too much of an issue, to be honest. Personally, I've found all forests to be a bit similar to each other in layout, weather it be Berry Forest from FireRed and LeafGreen, Petalburg Woods from Ruby, Sapphire, and Emerald, Ilex Forset from Gold, Silver, and Crystal, or Eterna Forest from Diamond, Pearl, and Platinum. They have never payed enough attention when it came to making forests, as they seem to go towards the lazy path and base them off of each other every time. d: