Cyber attacks - a problem?

With all the stuff in the news about the attack on TalkTalk's computers and the talk of security patches being applied to the Club web site........how real is the danger?

This is a serious question, as I don't have the expertise to know the answer. But it seems to me that these criminals could steal our names, addresses, bank name, account number etc........but surely they would need the password to access our accounts?

Am I correct in saying that the Club, TalkTalk, Amazon etc won't have our passwords, or are they also stored somewhere and available to the villains?