I enjoy putting together BP's and improving the habitat of a local lake. I have friends that do the same and we share pile for pile with certain rules like don't share or don't share with others who don't put in the effort. I do have some that no one else knows about but by doing this, I have twice as many piles I can fish. And yes I have seen others fishing piles I have built but am sure I fish a few of theirs as well so it is all good. I just feel better about myself because I have put in the work to enjoy the sport while improving the habitat.
^^^ x 2
Back to the original question "Which one takes more effort; building and sinking brush piles or roaming the lake looking for them?"
It takes much more "effort" to put out ones own piles.
A lot goes into putting out a productive pile. Collecting or buying weight material, cutting trees, bamboo or collecting or buying PVC, loading all this in the boat and hauling it to a lake and dropping it in "just the right spot".
Pulling up to that spot/spots a week later with a couple of wounded warriors or handicap seniors and wacking a mess of slabs,,,, priceless.