Its because it is! 
The main rain fade problem is not at the dish with rain, it is what the signals are passing through. Heck most of the time I get rainfade it is not necessarily raining or exactly where I am, it is where the signal is passing through the clouds and vapor.
If you still want to do like in those pictures, there is a probably much cheaper and locally available product..Rain X. Does the exact same thing of beading the water and making it roll off easier (it is made for windshields and glass).
The main rain fade problem is not at the dish with rain, it is what the signals are passing through. Heck most of the time I get rainfade it is not necessarily raining or exactly where I am, it is where the signal is passing through the clouds and vapor.
If you still want to do like in those pictures, there is a probably much cheaper and locally available product..Rain X. Does the exact same thing of beading the water and making it roll off easier (it is made for windshields and glass).