I think this (Rumble/Frenzy/Dave) issue is one big sick private joke within the Hasbro offices.
Hasbro Marketing Exec: Watch the forums explode when we give them a Rumble toy that is blue!
Hasbro Toy Designera: Eh, the mould is the same, why not. We will be releasing Frenzy as well right?
Hasbro Marketing Exec: What do you think would happen if we let FunPub do it?