Every game has it: crap gear the devs included just to Piss. You. Off.
First off, the shivs in Last of Us were NOT useless. Frustratingly fragile, yes, stupidly fragile, yes, mind-bogglingly, moronically fragile, yes, but NOT useless. Especially when you caught all the upgrades, they were quite handy to have around. And you could tape them to a club for an even better weapon.
(And now I want to play Last of Us again.)
That whole Half Life 2 flashlight thing was COMPLETELY bogus, I agree. They fixed it in one of the Episodes, though, so everything turned out alright in the end.
I myself had a run-in with a totally useless piece of gear in Shadowrun: Hong Kong, released two days ago. On your first real run (after the beginning gun battle / tutorial), you can find a simsense chip that is a Mission Item, something reserved specifically for quests.
Only, unlike every proper Mission Item, there is NOTHING you can do with this chip. No person you can talk to, no place to plug it in, you can’t even slot it yourself, even if you DO have a datajack. (And I was in the mood for a little Neil, the Ork Barbarian.) All it does is sit in your inventory until you exit the mission, thence to disappear COMPLETELY.
Nor is it just me. The Steam forums for the game are filled with people who’ve been mystified by the presence of this TOTALLY useless bit of exotica.
Well, mystery solved: Whether by bug or by design, apparently game devs just love sticking in useless pieces of gear for us players to haul around.