Random fact time (assumed to be true - I forget the book I read it in):-
Apparently King Louis XIV is to blame for people having grass/gardens at their homes.
The idea being that because is was so rich he was able to make a statement with the Gardens of Versailles along the lines of "look at me, I'm so wealthy I can afford to leave all this land unfarmed and not worry about the lack of produce/animals on it" - i.e. it worked as a status symbol.
This then passes down to French nobleman, who in turn pass it down to the middle-class and so on down the chain.
So having a lawn becomes a status symbol and an indication that you have money to spare (and are generally better than the peasants who need to farm all their land!).