I loot everything, even rotten food and bones and rags. That's mainly because clicking the 'take all' button involves less mouse movement than clicking the cross to close the window. Searching all containers takes too much time as it is. I do skip vases (except for those in the grymforge area that I know to contain something) and bottle racks. And I stubbornly keep on opening herb hangers, because, by golly, I can see those herbs hanging there, even though the game tells me there is nothing to take.
In my latest playthrough, I have also taken it upon myself to collect all explosive barrels (oil, firewine, smokepowder) and send them to camp, with the intention of seriously blowing up whomever turns out to be the end boss.
