Do notice that most of the RT careers (Rogue Trader, Arch-Militant, Astropath Transcendent, Missionary, Navigator, and Voidmaster) have the option of starting with weapons found under Melee Weapon Training (Primitive) yet none start with that Talent without spending xp (or coming from a Death World).
All except the Navigator begin with Melee Weapon Training (Universal), which covers their starting gear. The Navigator is given a staff and no training, but arguably that's more a symbol of office than a weapon in their case.
I agree with others that a simple House Rule is needed: you select your starting gear, and are given Exotic Weapon Training (That Item). Hopefully most GMs wouldn't take issue with that.
I also missed Spook's earlier thread on this very issue. Sorry about that.