a bit yes - but then again it's a unit Humanized, easier to read, more accessible I guess.
nor does the average person know the exact radius/diameter of the earth, jupiter, or the sun, but we often see references to the earth is a fraction of jupiter and that the sun is some large number of jupiters.
I could understand wanting to explain what AU stands for, and what an Astronomical Unit represents, it just seemed weird to then convert everything into percentages as well