I think it's logical--in fact, I think there should be a repository of PQRs run by the electrode manufacturer since there's no requirement for the same equipment or people to be used for production as were used for the PQR, but what's logical and what's required are not necessarily the same.
For D1.5, some owners have interpreted the requirement to be if the different locations are audited separately by AISC, they need separate PQRs. Some have interpreted it the way you have. Bottom line, as the owner, you (well, maybe not you personally, but your agency) are kind of free to decide that for yourself in the absence of an official ruling from AWS (and, really, the owner is even free to override AWS in the contract). Not that I'm saying there's no official ruling; I just can't find one in the materials to hand. That "separate AISC audit" thing comes from someplace, I just can't remember where.
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