Because you like Donkey Kong in Donkey Kong
Dorothy Gale is a down-home Kansas girl in a bizarre fantasy land with beautiful red shoes. See them in The Wizard of Oz.
Betty Cooper seems like a sweet girl, but she also has a dark side and can go beyond what's safe or sane. See them in Archie Comics.
Chewbacca is a loyal co-pilot who won't hesitate to rip your arm off. See them in Star Wars Series.
Nemo is a small fish in a vast ocean, but he dreams of seeing it all. See them in Finding Nemo.
Bart Simpson is an aspiring juvenile delinquent who doesn't want you to have a cow, man! See them in The Simpsons.
Viking Astrid Hofferson has it all: brains, brawn, and some killer braids. See them in How to Train Your Dragon.
Po is a clumsy, friendly panda who likes to take it easy. But now he's expected to save the world? See them in Kung Fu Panda.
Greg Heffley will be famous someday, but now he's stuck in class with morons. See them in Diary of a Wimpy Kid.
Aldous Snow is a rock star who plays hard and parties harder. See them in Get Him to the Greek.
Stuck on a lifeboat with zoo animals without food and fresh water, Pi Patel uses his intelligence to face the greatest test of all: survival. See them in Life of Pi.
Just call Jeff Lebowski The Dude. Or His Dudeness, Duder, or El Duderino if you're not into that whole brevity thing. See them in The Big Lebowski.