Ha ha, that reminds me of explaining to an interested child in Greece that the pistachio bushes around us produced pistachio nuts, of course, but that the big fat swollen, reddened leaves it bore were caused by parasites - I tore some open to show him the creatures crawling round inside. But his father interrupted to say that this was all nonsense and it was a bush that produced two different kinds of fruit, nothing to do with parasites. I was a little offended, but there was no point in arguing. However, the child had seen the creatures, did not contradict his father, but I could see that terrible doubt that comes over children as they grow up and gradually realise that their parents don't know everything.....
However, that fruit looks to me so like a legume that I wonder if the bush/leaves actually produced it. Could some bean type thing have climbed into the bush and caused confusion?