Very fair question, I had the same thinking two years ago. Since then I got interested in amateur radio, and in particular low power, portable operations as well as homebrewing transceivers.

Using only 5W when conditions are right can work from Australia around the planet using a $30 radio and a 20m wire antenna thrown in a tree.

Also, while its definitely possible to homebrew equipment that transmits voice, morse code is much simpler as you are approximately connecting power from an oscillator to a small amplifier (a couple of garden variety transistors works just fine here)