Geography Mock Watch

Hello guys, my name is Chittesh.
I've got a mock on Wednesday, I think I've left it to late with this particular subject, regardless of me being quite good at answering the questions - hopefully I'll manage because I learn quite fast.
I've realised that in many of the topics there are a lot of case studies. Now, they are never questions which ask for case studies - unless it says "Explain the impacts of climate change on a developing country, give an example...". My friends have told me that it is important to memorise case studies as you can use them in your answers and it'll gain your more marks, is this true, and if so can you give me an example? If not, why do we actually memorise case studies?

My exam board is : GCSE Geography - Edexcel B
My exam is on: First 4 Compulsory Topics of Unit 1 + First 2 Compulsory Topics of Unit 2:
Restless Earth, Climate Change, Battle of the Biosphere, Water World & Population Dynamics, Consuming Resources.
I've completed Restless Earth. Climate Change is pretty easy - mostly common sense, I've barely revised it but got a hang on to it. Battle of the Biosphere - nearly done. Water World - haven't touched. Population Dynamics - doing currently. Consuming Resources - haven't touched.

I just don't get what is the point of memorising case studies of volcanoes & earthquakes?