Because I don't ever hit them except by accident while using vi(m) so disabling means an accidental keypress does nothing rather than something I didn't want.

Because I don't ever hit them except by accident while using vi(m) so disabling means an accidental keypress does nothing rather than something I didn't want. (my main reason for preferring original ex-vi is that when I typo a command, it beeps at me, whereas in vim the typo is usually some completely unrelated but valid command sequence and then WTF JUST HAPPENED and argh)