When questioned about the easiness of getting all 1000 Gamerscore for the game, Jon Cartwright, Director of Production at THQ, stated that it was because children were the targeted demographic for the game. They wanted to introduce kids to getting Achievements.
"If someone's been playing fighting games for years then the Achievements in "Avatar" are not going to challenge them too much. But again, we're not targeting that gamer. We tried to focus on the thrill a young kid would get when he/she receives his/her first Achievement. We feel having some easier Achievements make the whole Achievement system more accessible to a younger audience."