I've always theorized that Ganon killed all of the children / young people in order to prevent future Hyrulean generations and that's why there are only old men and women (and moblins (and weird Mario people)).
They are all different characters: the remaining population of Lesser Hyrule after Ganon's invasion.
All Old Men/Old Women/Moblin Shopkeepers:
Eagle Old Man
Moon Old Man
Manji Old Man
Snake Old Man
Lizard Old Man
Lizard Old Man
Lizard Old Man
Dragon Old Man
Dragon Old Man
Demon Old Man
Demon...