This is to stop people buying Duty Free goods and not travelling? So how do you get out if you miss your flight? There was an exit last time I was through, 100%, it must have been removed as I remember filing it for future reference as a handy to know. There are always people who miss their flights every day, there must be an offical way to exit airside if you're not travelling. I mean they don't actually check the domestic arrivals, you could head to Sat 2 lower level then put a jacket and hat on and just exit with the hordes of arriving easyJet passengers (!) but I'm sure there's an official way.