You have it ass backwards. You expect to be rewarded for it so you spend time looking for shit you know you won't need.
Again, as said, you can complete the game with no items. also no skills. By your logic it is all a waste of time.
I'm afraid it's your logic.
You can tell by it befitting a
person.
My logic is that if your mechanics motivates actions that make no sense in the gameworld (crawling down every vent) with stuff that doesn't exist in the gameworld (XP pellets) then it has a problem.
The problem is that it sucks.
Exploration is a requirement by default
Don't be dense, you can beat DX with only a tiny fraction of possible exploration. This means that the vast majority of exploration is not a requirement, it's strictly optional.
so there's no harm in further encouragement.
So there is harm in further encouragement. Actually, the moment you start using the word "encouragement" in relation with something that clearly doesn't exist in the gameworld (because how do finding a barred room accessible only through vents makes you better at shooting or hacking? The exploration XP pellets don't really translate into anything meaningful, at least genocide encouragement in form of combat XP has some relation with combat prowess) is when you have a clear indicator that there are problems present - you use out of universe means to try and encourage different behavior than player would engage in given only the in-universe context.
The bottom line is that with a simplistic system like anything XP based you should only be rewarded for something you unambiguously want anyway. Critical path nodes are there, so is finding significant optional information, significant universally useful items or completing universally desirable optional tasks. Finding a particular vent or novelty way into a room is not.