Even when I'm not playing permadeath noportals I tend to move my early bases quite a bit and for me to use a pure kite defense requires clearing a nice swath of the perimeter, maybe some leveling, etc which I'd rather just skip when even if I'm kiting I need something to stop or slow down raids with multiple trolls just in case I lose one from the kite.

Logs fit the bill since I can recycle and cart them off as lumber/coal later.

Just to be clear, my early bases aren't usually on leveled ground except by pure coincidence. Main building on stilts, a ramshackle stake fence to block LOS, and something on the perimeter to slow down the raid mobs is pretty much all I bother with. Will not win any art contests lol.