I don't know why you guys are surprised, uneducated people with lots of money...
Very few of these star youth players turn out to be okay mentally, this is accentuated when they come from a poor background.
Ronaldinho,Adriano,Quaresma,Ronaldo(C.R)... I could go on and on.
If they didn't have football these people would probably be taxi drivers, cleaners etc.
Nothing wrong with these professions but very few of them are actually smart.
Sure exceptions exist: Socrates, Arshavin, Alcantara but they are rare.
Balotellis are much more common.