Even at domestic NTL, the secure area is for departures only, so you have to ask to leave if you don't catch a flight. It's not that difficult.
Yep, I've had to do this in India (DEL), which uses a similar secure area process for even domestic departures. It was far from unheard of, they had a clear process. As with many things in India, it did take a while but they got me through. In my case, I didn't want to travel as my meeting at the destination had cancelled - it was purely my choice - but the airline and airport staff gladly helped me get out.