why would they crap? i guess to make room for more brains. but it wouldn't be a digestive process right it'd just be goopy brains going wherever there's room so more goopy brains can come in. they'd probably go thru the pooper in the first week at least of decomp but at some point, another section might rot out more and the old brains get out through there.

basically zombies should have ABC human brains coming out their bullet holes and i can't think of a good reason no zombies have so far. sounds gross af