tefilla - Why are the words כהיום הזה mentioned in Al Hanisim for Chanukah and nowhere for Purim and Pesach?

Why are the words כהיום הזה mentioned in Al Hanisim for Chanukah and not in Al Hanisim for Purim or at another appropriate place (in say the brocho of אשר גאלנו) for Pesach?

Credit to Alex for suggesting this question here.