iTunes storing

When you add content to your iTunes Library, under the "Get Info" section, why does the "Sorting" field automatically populate, even though there is no visable evidence in Finder : ?

I have two files... both Sorting are populated, i can not leave it blank, but in Finder there two completely different :-

 

Ya, i know, but the screenshots are just to tell the difference.

Both movies, have "sorting" populated, which you can change in itunes after the fact, but they are populated on import.

However, in Finder one displays the "title" tag of that's populate, while the other doesn't.

Why is this ?