When I think of an easy, crowd-pleasing thing to bring back from Liechtenstein, local coffee beans from Liechtenstein is a good pick because it does not need much explanation when you hand it over. It is a good one because people can try it slowly at home, and it makes a nicer gift than a mug with a place name printed on it. I would look for it in a proper local supermarket, covered market, deli, pharmacy, gift shop or small producer rather than leaving it until the departure gate. Back in the UK, it is worth checking specialist shops first because they often stock a better version than a broad marketplace listing. I would rate it higher when it is locally made, clearly labelled and easy to use at home, and lower when it is just tourist packaging.