Why vi binds ^/$ to move to the start/end of a line - while (”im mirrored”);

vi, vimRecently, my friend asked that: Why does Vim bind ^/$ to move to the start/end of a line? It's not easy to type, isn't it?Yes, it's an understandable question. I also wondered about that when I began to use a vi clone. But now, I realized from my long experience with Vim. I answered that: Because you'll almost never use them.Suppose that you use ^/$ to move the cursor, then what do you want

[bonar]

なぜ vi は ^/$ を行頭/行末にバインドするか。使わないからだ。

[janus_wel]

I consent this entry, but which vi and regular expression exists earlier...?