Profound question of the day

Why are open-top dustbins round in shape? - yj and I
Is it just so that people can miss by throwing it into the gap between the round dustbin and the corner of the wall? Was the first dustbin designed by aliens?
These are all perfectly important questions that must be answered by mankind. Yet, a cursory search of the exact phrase on Google yields no results. Mankind has been asking all the wrong questions.
So it's up to me to put forth my theory.
Maybe, we've all been conditioned to treat open-top round containers as dustbins. Thus, if you leave a round bucket in the middle of a public area, you're likely to get some idiot spitting into it. But if you put a open-top square container there, it might just be treated as an art installation! Hence, the manufacturers make round dustbins so that the dustbins will not be confused for something else, such that they can fulfill their true destinies as dustbins.
However, why do we treat open-top containers as dustbins in the first place? It is highly possible that it was mentioned somewhere in the Bible. It is also possible that the first dustbin was a gift from a higher being. For purely rational reasons, I prefer the second explanation.
It goes like this. The world was once clean and dust-free. Then, a higher being bequeathed to mankind two things:  Dust and a open-top round dustbin (to hold the dust of course). The higher being must have done this because he was bored. Blogging probably didn't exist then. Well, dust in those days was one big vast mass that was round in shape. The higher being said, "Do not touch this mass of dust. If you touch it, it will disintegrate and drift all over the earth". That also happened to be the moment reverse psychology was invented. To cut a long story short, some asshole decided to touch it, and in so doing became the first terrorist. The dust drifted all over the world, and we have been manufacturing round open-top dustbins to contain the dust ever since.