Usernames are not always similar to email addresses. In fact, if you are "foobar@example.org", you might find that someone has already claimed the username 'fo

Usernames are not always similar to email addresses. In fact, if you are "foobar@example.org", you might find that someone has already claimed the username 'foobar' on Amazon. So I believe your parent commenter's point is that he wishes he could associate both a username & an email address (or at least a comment field) with each entry in his password manager.