I'm not sure why, but I like bars that have serial numbers. e.g. Canadian 10oz. There is just something nice about having an individual traceable serial number, so much so that I'm thinking that maybe it's serial number only for me from now on. Does anyone else only, or mostly only touch serial numbered bars?, and if so, why?
the primary advantage of serial numbers is theft. You should ensure you take photos or at least now down ask of them so they can be circulated at local pawn shops and bullion dealers if they ever get stolen. theoretically they should be used to confirm provenance, but it wouldn't be hard to make fake bars and copy the numbers off another bar, the odds of those two bars ever being checked against each other are very slim.