Grass is a plant that do not grow naturally in a non-constructed terrain. So should have been planted, so is the landcover or surface of another element. Said Park, Garden, Traffic Island. My point is that could not be assumed that any empty green area is landuse=grass. Normally is more weed or scrub than grass
Вторая половина этой речи, говорит о том, что человек никогда не видел спортивные карты леса с рельефом, зеленками, топями, канавами и тд