Maybe it’s because they’re doing something different.
Maybe you’re not looking at it close enough. Things do look different from a distance, you know.
Maybe it’s a different kind of grass; a kind you haven’t tried.
Maybe you missed it when they dug it all up and started all over again with different seeds.
Maybe they’re using different fertilizer.
Or maybe, just MAYBE, they’re looking at your grass and thinking the same thing.