Infinite weapon repair kits OMG! That makes repair skill irrelevant tbh.
So does Old Lady Gibson, it's just not as obvious.
I don't know why people make the Weapon Repair kits though.
One Sierra Madre token = one unit of old world money, which is worth 10 caps. So basically, if you win big at the casino there and cash it all out for Old world money, you can get 100 grand worth of caps. Sure there are certain weapons or weapon condition levels that are too expensive to have an NPC repair, but 100 grand seems a lot more flexible than having 100 weapon repair kits that aren't worth a darn. I'd just get 10-20 repair kits and cash out with the rest.
Why would you worry about conserving or converting sierra madre chips though? They're infinite.