At times it is necessary to eliminate plants from a large area - in Los Angeles, this is most often grass - and sheet mulching is the way to do it. Here is a lovely post about ridding a Bermuda grass lawn - one of the most persistent weeds a garden can have. Without chemicals and without a lot of heavy sweating, any lawn can be history.
This technique not only doesn't use chemicals and hard labor, it also leaves the soil in much better condition than it was as a lawn. It seems to me to be a win/win/win situation. It does require patience, but, while patience may be a virtue to the general population, in gardeners it is essential!