The advantage is a clean design. Tear no. 1 was built fast. I drilled a hole in the side of the t/d, put on an outside recep cover and when camping would open the cover, push through an extension cord and hook it to a power strip.
It got old after a few dozen times, plus it was an entry point for fire ants down south (where we sprinkled comet cleanser around tires and tongue jack to keep them from coming in).... so I upgraded to the normal route..
Anything that you have to do continuously becomes a chore if there is an easier and more convenient way to do it.