Do you really need to know exactly how many seats there are on a 737-800?
I think you need to have an idea. You will probably never need to know the exact number of seats on a 737-800, but you need to be aware of the size of the aircraft, and the number of seats is related to that.
In my opinion, they ask us to thoroughly study the document in order to test our motivation. If you are motivated, you will learn the data no matter what. If someone is really interested in becoming an ATCO, he or she will surely have to spend many hundreds of hours studying all sorts of subjects, so the Stage 1 ATC paper tests whether you were interested enough in air traffic control
