Why would you want someone want to purchase a piece of undeveloped land? The positives are numerous and unique to land. How many other investments do you know of that are a finite resource which you can actually use?
Unlike a house land does not require maintenance. No headaches!
Land is a great investment to pass down to your heirs
As a finite resource land will inevitably become more scarce as population increases. (and value may go up too!)
It is surprisingly affordable. (Often cheaper than a car payment)
A place to build that vacation home or just take the R.V.