It does not sound plausible to me that a camera can break a card by reading or deleting it, that it might happen because the card was faulty, and you just happened to be writing or erasing something at that moment, that could be... But the camera toasting the card... Don't thing so unless there is a huge design fault on the camera and probably most of use would have the same problem and a huge class action against Canon would be in order by now.... There are no moving parts like in HDDs so it is harder to break, but for sure there are parts that can go wrong, I had a Sandisk Pro Extreme going bad, totally dead, but just sent it back to Sandisk, had it replaced in about 10 days, but would never blame the camera for it, of course it is going to break while you using it :-)
Hope you get it replaced. Good luck!