The Wastelands (Not in game anymore) were areas populated by very little of anything except trees. A large area of the map is made up of wastelands, as Facepunch Studios has yet to fill over 95% of the in-game map. Most of the time, getting to the Wastelands can be pretty tough, but getting back is even tougher. There are no Rocks or Wood Piles. This makes it a negligible place to start a base unless you go on regular resource runs to the populated areas and don't want to be raided.
Players rarely visit the Wastelands due to the high chances of getting lost and low chances of finding anything good. This makes it a good place for a high security base. If you have a large quantity of metal, food, guns and other valuable stuff, you are unlikely to be found and even less likely to be raided the further out you build in the Wastelands.
The downsides of living here are that if you run out of resources, you've got a while to run before you reach anywhere you can gather from. Running out of food can lead to starvation and running out of ammo during a raid means that you're almost certainly dead.
Some have been known to survive long periods of time with just Wooden Doors. Because the area is so desolate that there is very little reason to go there.