What's the use of nicknames for a contact?

I set up all of my contacts (tediously) to match their exact names on Facebook so the profiles and pictures will sync properly. As I was doing this, I also set up nicknames in the contact profiles for all of these people, assuming that it would show me their nickname either in the contact list, when they call/text, or preferably both.

Unfortunately it doesn't seem to do anything. What's the point of the nickname? For instance, I had to use my parents' full names so their FB profiles would load on the phone, but even though their nicknames are listed "mom" and "dad", I never see those names used anywhere, besides just being listed in the nickname field when I edit the contact.

Anyone know what the point of these is or how to properly utilize them?