Yes, that is one downside of carbon fiber frames, they can be repaired unlike aluminum so in the long term you have to weigh up the pros and cons of which is better. If you really are concerned with the environment and want a frame that lasts and can be repaired, steel and titanium is the way to go.I hope no one ever finds out! I have also had 10+ aluminum mtbs and only 2 carbon mtbs and the only thing that I know for sure is that CF will end up in a landfill and AL can be recycled. Other than that, at my age and skill level, I have yet to notice a difference except in my bank account