Well, I don't know if I'd call it Rip-Off so much as mutual agreement. I thought in the fantasy world it was agreed that certain beings looked and behaved a certain way. Like imagine if in some books Dwarves were 12 foot tall & stringy? Or fairies were as big as dragons but only in some books. It would be too confusing. All this lore came from campfires and hearths of long ago .... so let's respect it, I say.
Of course there always is room for improvisation and creativity ... especially among Dragons. Truly, I believe that the earliest of Neanderthal men saw the last of the dinosaurs in person, perhaps even helped hunt to extinction ... and carried the story of the magnificent beasts even up to this day. Fire=breathing?? If they were swamp dwellers they could have been methane-based creatures.
***This has been an Agent Mulder moment = I want to believe!