Can see it would be of use if you towed with different vehicles regularly,but most only use 1 tow vehicle. Plus it looks like a rather messy way to connect. If you do tow with multiple vehicles you would need to have different adapters for each type of plug.
Hugo
"If a man does not keep pace with his companions, perhaps,it is because he hears a different drummer. Let him step to the music he hears, however measured or far away". Thoreau.