Because they embody earnestness. When they run to you, well, to me, because I am the Food God, they barrel. They get excited about stuff. They're enthusiastic and curious.
They are incredibly attuned to their environment: they hear everything and are constantly on the look out, being the Prey Animals of all Prey Animals, the Underdogs of all Underdogs, and they know it. Given how attuned they are, I think they are probably predisposed to madness, given the food factory business.
They are primitive and of the ages: my chicken is Picasso's chicken, is Ghengis Khans' chicken, is Moses' chicken, is William Carlos Williams' chicken (the latter: I think he got it).
Because they're dinosaurs.