Complete foolishness, but every region has its own customs and games. For example, in North Africa, there is the 'sheep fight,' where they bring two rams to butt heads against each other, and the winner earns money. and some people even bet on the winner..
I didn't even know that was a thing, honestly. But considering there are folks willing to bet on people punching one another until unconsciousness, then it makes sense they would also bet on ram battling each other. Though, I must ask: those male sheep fight untill one of them get hurt or die to its injuries? Because that's a determining factor to know how much animal suffering is related to betting/gambling.
At this point, and after seeing that picture you shared, I would feel more comfortable betting on robot fights.