this is obviously bs, the lawn thing is mostly a north-american obsession. most people here in europe like shade and thus higher vegetation in their gardens.
But once there were public lawns in cities, people found practical uses for them. Many popular ball games are still played on surfaces that resemble a lawn.
That same distinction makes sense for private lawns. Do you have a decorative garden, because your lot is larger than what you actually need? Or is the lawn a practical surface for open spaces you occasionally use?