No. Way back when the first vendors of the kind were introduced we were specifically told these items are supposed to add to the collections just as well as the ones from the Cartel Market. I think there even was a specific patch early on that added that functionality. Once the bind timer runs out, the pieces should add to the collections even when mixed and matched with the pieces from the packs, that's how it's supposed to work.
So if I understand correctly, are we supposed to consider the items from the Contraband and Bounty rep vendors (Thana Vesh set, Mask of Nihilus, etc) as the ones that are "bugged" since they do unlock those items and complete sets on the Collections?