I remember complaining to my dad about this exact thing saying that people just look it up in real life. He told me that in the end, the grade that I get will only tell future employers that I am more or less “teachable” compared to others.
What you studied, specifically, didn’t matter. It’s how well you learned the material in a short period of time, then cranked out correct answers in a time-pressure situation.
If you can do that quickly, you get a better grade, which tells people that you are a better candidate for a position.