On all tickets, there is a area "Sub-ticket" with all sub-tickets title 

Only title; submitter name and date of last modification are displayed in this area.

Section & Category names are (for me) required to understand the object of the sub-case.

Example :

✈\747 - Sydney

Section : ✈

Category : 747

Case title : Sydney

Case title displayed without section & category doesn't means anything

Add the SECTION\Category under the sub-case title