I think the simplest answer to the original question was that there was very much a market for it. No matter what kind of car I'm looking to buy, there is a higher performance option available. Keep in mind too that GM, Ford, and Chrysler were some of the largest companies in the world at the time and riding waves of huge profits. The bean counters had yet to really come in and start standardizing everything as well. Chevy, Buick, Olds, and Pontiac all offered 350 engines, but they were all different designed by each division. Buick, Olds, and Pontiac also had 455s...but all 3 were different motors. Start moving to the mid 70s and you begin seeing discontinuation of engines and sharing amongst brands.
But for a brief few years as Warren Oates who played the character "GTO" in the movie "Two Lane Blacktop" says..."Performance and Image, that's what it's all about."
But for a brief few years as Warren Oates who played the character "GTO" in the movie "Two Lane Blacktop" says..."Performance and Image, that's what it's all about."