User blog comment:D2r/Unanswered Questions of Redwall/@comment-1399757-20110213144312/@comment-1479469-20110214215800

Going over the walls is a good way to get an arrow right up where the sun don't shine, I think. :p

As for latrines; yes - I assume that happens, too. But you have to admit that it's left pretty vague - heck, in months-long sieges, what would they do with all the waste, without plumbing? In real life, latrines fed into the castle moat (moats were truly vile - the water was basically sewage), but Redwall has no moat, so...

Actually, come to think of it, the same question applies to Salamandastron.