I dont destroy the fuling structures.
Rather the opposite, i try to do as little damage as possible on their buildings.
I place workbenches in cleaned camps to prevent further enemy spawn.

I use one camp with two tar pits nearby as barley, flax and tar farm.
And on the moder island i occupied an fuling stone tower, built a workbench and portal inside and use it as scout outpost to explore the island.

You can also hide yourself in their shacks or roofed spy towers if you accidentally lured a deathsquito.
They cant enter buildings because of their flight pathing and lose interest after a while.
And as far as i observed, they do not attack the buildings if they cant reach you within attack range.
After my countless deads in plains, i developed the tactic to sprint naked from cleaned camp to cleaned camp to come into range of my last gravestone (only fulings must still be avoided).