From someone who has store-bought cd's and has made/burned cd's.........it just depends on how a person handles/treats them. I handle our cd's and dvd's very carefully! Unless absolutely necessary, I never touch the recorded side. We've rented dvd movies that had finger prints all over the recorder side and I use a "glasses cleaning cloth" and wipe away the finger prints. Some people leave their music cd's in their vehicle in summer heat and then they get upset b/c the cd ends up being warped. We never leave cd's in our vehicle. All of our cd's are in cd holders or cases.
Use to have all of our photos on cd's, but found out about "flash drives" (USB) and now have all of them on those (flash drives).
Yes, cd's and dvd's will last quite a while if the owners take care of them.