Yea but everyone learns it in school, and its pretty intuitive, meaning its not hard to forget. So I still don't get it.
Yeah, and I learned in school which French verbs should be conjugated with être rather than avez, and I'm sure that to people who actually use French regularly that's perfectly intuitive and easy to remember. Yet I never use this in my daily life, so I've completely forgotten them all.
And I can't think of any instance outside of my work where knowing about operator precedence was actually necessary.