Also... I'm pretty sure it's not just Sam that ends up with dropped loot in my game. I go through all my characters to find who's carrying.
Yeah sorry. I did only one anecdote before, thus said in Sam's inventory.
Tonight I had one regular mission and one training facility attack against Survivalists. In both cases there was loot collected from the battlefield (hadn't cross-checked with all the dropped backpacks' content though). So wasn't able to recreate so far. But at least it's clear that what Nomad reported won't happen on each battle. Will keep eyes open.
Shouldn't draw conclusions from a few tries, but so far it seems, indeed, that they are less prone to drop firearms during the battle. On the regular one they dropped only ammo and trauma kits and on the facility one dropping was: two knives + bat + one pistol + ammo + trauma kits.