A common sight in the marsh: herons and egrets stalking their prey.
This part of the marsh is flooded from all the recent rain, and the foraging area is congested with once weedy vegetation that has since died. This might be fine for foraging on critters hiding in the mucky bottom, but it makes flying to an observation perch challenging when the bird tries to navigate through the dead sticks.
These big feet are meant for something else entirely — wading. Long toes that distribute the bird’s weight evenly on an enlarged surface area prevent herons and egrets from sinking into the muck, as they stride along the marsh looking for anything moving.
So, big feet may be disadvantageous in perching on small stems, but of great advantage in wading along mucky marsh beds.