Big sports events are the "circenses" part of "panem et circenses" [1]. Fun fact concerning this: the German word for "entertainment" is "Unterhaltung"; thus it can be argued that the purpose of entertainment/Unterhaltung is "unten halten" (to keep at the bottom), i.e. to keep the mass of the populace at the bottom, or in other words: to prevent the mass of the populace from coming up.
> Would anyone watch these robots in competition?
I have seen robot fight competitions both live and in videos, and I have to admit that these are not boring to watch.
So yes, with a proper marketing I can easily imagine that lots of people would love to see broadcasts of some robot competitions.
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