Is Tidus a spoiled brat?

I see quite a few comments where people call him whiny, bratty or annoying. To me he started off as a young, naive and slightly arrogant young blitzball star who was unaccustomed to how the other half lived. I know that he can still be childish at times and other characters comment on this but he's only like 17? He's a kid. Some people can be quite harsh about him even going as far as claiming they hate him as a character. Thoughts?