Orville Slump elaborately arranges the deaths of innocent and unsuspecting monkey children to steal their food.This is a long shot, but most people probably noticed how uncaring Orville was at the supposed deaths of his "friends". Well, what if he planned it out. It's possible that the film takes place in an alternate universe where monkeys are advanced (similar to Planet of the Apes, but monkeys and humans coexist side by side, but the monkeys are treated as second-class citizens), and Orville comes from a rich family who despises the monkeys. Orville could get any type of food that he wants, but he is a sociopath who pretends to be friends with the monkey children. He gets to know them long enough to know exactly what they are like so that he can plan accordingly when the inevitable bike trip to the park happens. He then uses his parents' money to pay off people to "accidentally" kill the monkey children on the way to the park so that he can steal all their food (hence why his bike has a basket). That's why the steamroller just "happened" to come by at the right moment: because Orville carefully planned out every last detail of the film. The narrator could be Orville's inner voice outlining his plan as he goes over it in his head. The reason it sounds older is because Orville has always associated being wiser with being older, and he sees himself as wiser than the monkeys and therefore older. Once all the monkeys are dead or seriously injured, he eats his own lunch and disposes of the monkeys' lunches. Later, he just moves onto the next unlucky group of monkey children and again suggests that they go to the park for lunch, only for the monkeys to each suffer an unfortunate "accident". The reason why, at the end, the narrator says that Orville doesn't really want the food is because it's true. He doesn't really want it, he just thinks it's fun to indirectly kill beings that he sees as inferior to himself. Simply put, he's a racist sociopath and if he lived in our world then instead of monkeys getting killed on their bikes, it would be black people or Mexicans.
Orville grew up to be Professor BoboThe reason he's so much less-ugly? Puberty was quite kind to him.