Mostly for the thing we care about grass for: looking at and touching. We don't grow grass to feed goats. We grow grass for the appearance of grass. It serves no practical purpose in most places where grass is grown. Obviously it does have a place in nature, but not where you're putting artificial grass. The only purpose in those places was touch and appearance. It handles that fine.

AI is a perfectly good term. It's just an overused one. It was great when it was in academia, and everyone knew what it meant, or in a sci-fi story, and people didn't think it existed. It's currently been used as a marketing term. People hear it and think it's intelligent. It isn't. The goal of using it for marketing was to create this distortion. They don't care to inform people of the meaning because the only reason it's valuable is because of the confusion.