Sometimes it's just not cost-effective to dismantle and repair stuff like that - the time it takes to do all that outweighs the unit price of the item (that's what it cost Canon to manufacture, not the price we pay for the damn stuff!).
I had to do a similar thing once with a load of film cameras and lenses - it wasn't economical to send them back to the depot after we made the final transition to digital, so the bosses issued a local destruction order and we smashed up about 200 Nikon FM2n bodies, about 100 F90x bodies and the lens 'kits' that came with them - 24mm, 35mm, 50mm, 105mm, 135mm, 300mm and 600mm lenses (only five 600mm lenses though and I 'rescued two of those that were in mint condition).
Some of the kits I managed to pass on to a local college, along with some Jobo processors, a Gretag processor, eight DeVere 504 enlargers and loads of darkroom kit: dev tanks, trays, tongs etc.
At least three people on this forum benefitted from that...lol