only stumbling about these forums and when i read this again I have to correct you. Barbs never spawn at full warehouses on startup, They have 50% of their warehouse capacity which is always 500 res of each type.
well but thinking about it again, I am actually not entirely sure if it's 50% or 40% ... I have gotten so bad luck with barbs next to me in all recent worlds that i hardly ever managed to loot at full capacity with my first 2-3 hauls.