Understanding is also important when instead of getting rid of something/not copying some tactic you want to copy it. I once was in some cheap cinema where instead of the heavy red curtains they had some structures they painted red on the wall. My guess is that you have the curtains on the wall for a better sound quality, the sound in this cinema was really bad because of reverberation.

The only problem is that it's sometimes not possible anymore to find out why something is the way it is.