What creates a picky eater?

I received a bachelor's degree in child and family development. In my studies we talked about different cultures and their eating Habits. One think we never talked about however was the presence of picky Eaters in all Communities. So to you what creates a picky eater?

I can see Not being exposed to new flavors and textures as a child's, Maybe being over exposed to new textures and flavors and not wanting to try new things. Maybe its genes ? Or is picky eating more of a sign of privilidge, Being able to be picky where others are forced to eat what's in front of them.