You'd still get the map marker showing a filled stash.
But it was pretty disheartening first time through SoC, checking all these boxes and such I kept falling over, only to find they were all empty. Took me a little while to figure out that those short on-screen messages I sometimes got when searching a corpse were connected to those boxes and backpacks.
In CoP you fall over little piles of equipment without even a box to check. Often stuff is missing - grenades rolling away and such - and an incomplete one picked up can foul up the count in the PDA.
Even with mods that have NPCs filching stuff from stashes there are numerous that are far enough away from their usual paths to use as temporary stashes in SoC.
As for filling them all from the beginning, I see getting a stash message from a bandit as confirmation that I've killed a bad guy - he got that stuff from somewhere and, being a bandit, it can't have been morally obtained. Duty and Freedom messages are extra thank yous for shooting endless dogs, flesh, boars, rats and suckers. I don't shoot loners, but any messages I get from them are considered 'better I have it than the next passing bandit'. Military - only if they shoot at me, and they don't give many messages, but taken as the prize for winning in the bullet-slinging contest.
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