Walking down any suburban street in the US or Canada, you are likely to see long rows of lawns. No matter what the climate or the weather, the majority of homeowners seem intent on having their house sit in a sea of turfgrass. Where does this obsession with uniformly green grass come from?
Evolutionary psychologists theorize that, since humans evolved in a grassland area, we prefer that type of vegetation. Trees, they say, make us feel that predators could be lurking behind them, but grass makes us feel safe. Landscapers say that the lawn contrasts with other plantings, making them appear more dramatic. Historians point to huge lawns on English estates, which symbolized wealth and power ("I have so much land I can just leave some of it to grass!"). Landowners in the Americas wanted their homes to reflect this English design. Others say that the front lawn acts as a buffer between the street and the home, keeping strangers out of our private spaces without imposing walls. And of course, realtors always loudly cry "Property values!" as though no one in their right mind would buy a house one the same street as one without a standard plot of grass.
Michael Pollan publishes a great essay about lawns in Edible Estates: Attack on the Front Lawncalled Why Mow?: The Case Against Lawns. He suggests that the lawn is a vehicle of both democracy (everyone can have one) and conformity (everyone should have one). He also suggests that a lawn appeals to man's quest to subject nature to his will, since a lawn is about the most unnatural bit of nature possible. The grass always grows, but never dies or reproduces.
None of these reasons for having a lawn is really compelling (unless you are a true conformist or your Homeowner's Association is quite demanding). A lawn is one landscaping option among many, but is often chosen by default. I think many homeowners, tired of the upkeep of a large lawn, are starting to look for other options. My personal favourite is, of course, the edible landscape, but most homeowners in my area seem to prefer the un-lawn, where they simply cover the lawn area with gravel. If you are considering this, be aware that weeds will grow through landscaping fabric, and that this design says "Defeat!" But maybe even that is better than all that mowing.