I would like to have a Grovyle, but for the most part I don't think life would be any different. Animals can kill you now, you just don't aggravate them.
And keep in mind normal animals can still survive, because weapons from both sides are equally strong. There are animals just like Pokémon, you know? Pistol shrimps are strong comparatively, I would think there would be a bigger version of it.
So no disasters.