SpaceX is preparing the technology to land on Mars. While this particular rocket will not go to Mars, the next iteration will. There are no soft floating areas on Mars, therefore that solution will not work. This is also the reason there are no parachutes, etc. Vertical rocket landings work on Earth, Mars, the moon, pretty much all surfaces in the accessible solar system. So having a rocket that can land vertically, refuel, and take off again is important for space travel, and that's the primary goal here. You can think of the Falcon 9 rocket and its tests to be like a revenue-generating prototype, so they're testing a bunch of future technology when they do these landings.