Ok so a spider's main diet is flies right?
Athena's mother, Metis, was tricked into turning herself into a fly by Zeus who then swallowed her. Metis gave birth to Athena in Zeus' head. Athena had the weaving competition with Arachne (a story we all know) and turned Arachne into a spider. All spiders are Arachne's children, Arachne hates Athena and targets Athena's children and Arachne's children also do that. So what if they eat flies because that is what Athena's mother turned herself into? So they eat flies to get back at Athena for what she did to their mother. Am I crazy or is this actually logical?