Except that they don't realise that real currency systems and banks are generally secure and safe.
Banks are safe, indeed. As long as they don't do stupid things like sub-prime loans or any kind of high-risk loan with most of their money, they'll remain safe. I should know as my line of work has mostly been in the financial sector, including banks.
Any currency system, however, is as stable as its backer. My country's currency (MXN) has ups and downs, so most people would rather have their life savings in something that doesn't have sudden drops every now and then. Bitcoin itself has been very volatile and as such is also not the currency I'd use for my life savings … though I do wish I had kept my 0.96 BTC I had last year (of course, NOT in Mt. Gox).
Interestingly, Mt. Gox ceased to be relevant to me when they were cut off by OKPAY. That was my only easy route in and out of that. Maybe it was the universe warning me to get out of there?