As a proud Norn Irishman I've always been a bit miffed when we have "Team GB" at the Olympics. I know it's all about branding but it does exclude one of the nations in the UK. The same when I see car insurance adverts on TV that have in small print at the bottom of the screen "Excludes NI".
Admittedly, those in the province don't do themselves any favours by having separate legal and licensing systems. 20 years ago I moved to England for work and bought a car in Coventry. As I was staying in a hotel, and didn't have an English address, I used my parents address in NI for the purchase. Six months later I went to re-tax the car only to be told at the post office that the car had been exported - to Northern Ireland. How can it be exported to the same country? I had to re-import it and only then could I sort out the tax.