Which is going to be a huge limit on sustained value/adoption, for better or worse. Bitcoin's rooted in the community most capable of stealing it.
MtGox has even given away free YubiKeys in the past to help keep people's accounts secure. Does Chase or BofA anyone else offer that kind of security? :)
https://en.bitcoin.it/wiki/Cold_storage https://mtgox.com/press_release_20120215.html
There's nothing stopping anyone from setting up a bank that handles your bitcoin transactions, and therefore can reverse transactions between two parties.
Replace "Bitcoin" with "Dollar" and you see how strange your statement is.
Bitcoin is anonymous, so I could transfer my money to my account at another bank, report fraud, and the bank could never know unless the other bank told them. If the other bank tells them, or you set up a centralized register of transfers or accounts, you're just mirroring the current systems.
Bitcoin doesn't have The Man, so there's no motivation not to do so fraudulently - what's the worst that happens if a bank realizes you're trying to defraud them? You've already moved your money elsewhere.
Chase has a thing where it texts you a code as well.
Not to mention the costs that security brings, a friend of mine is locked out of what is now $50k worth of bitcoins, just can't remember the password on the encrypted store.