To be fair, there are those here that know nothing or close to it of the cultures and deep lore of the settings' other races like Andorians, Deltans, Vulcans, etc. (Like me, as an example) Humanocentric is most of what we recognize.You assume that double book accounting isn't banned because it makes it harder to embezzle, or pull a great many fiscal shenanigans in general.
We get hung up on it explicitly because of that tendency, which tends to make a surface level look at the Federation look uncomfortably humanocentric, especially in combination with the TV Show Budget meaning there are fewer (visibly) non-human Starfleet people than there really should be on screen. Our attempts to push away from that tendency are very much attempts to more accurately describe the Federation as more than "Earth with extra bits for flavor" here.