Duty free means the products sold in those shops are exempted from taxes. The misimpression that such products are cheap is wrong. Not all duty free items are worth buying. You have to be discerning when you travel abroad. Some airports have very expensive duty free stores.
True, one should always read between the lines on stuff. I think the real truth is that some things are a good value - but obviously not everything. However, though, some of it has to be worth something - or where does the attraction come from?
I never thought Duty Free had cheap products and I rarely bought them in it (I think I can count on the fingers). That place was never my cup of tea anyway.
In the middle east the duty free is really cheap, in the UK it's not that cheap, and in the USA it can be cheap. For luxury goods it is because they are rarely discounted so it's worth it for a big purchase. I think if you shop around on the airlines, they can offer some deals plus additional airmiles if you buy too.
