Well, but the thing people who do online transactions "do" enter certain passwords online. And for an active attacker it is quite possible for them to direct you to a "secure" site operated by the hacker.
You can type your bank's website hoping to do some transactions, but without you noticing you might get redirected to a shady website. You might get the cute padlock and everything, but unless you verify the certificate to ensure that it was for the company that you specified, you might be in some trouble

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What I was getting at was that when u do so many transactions in a short time, sometimes u get "lazy" and forget to check each certificate manually.