It's news to me that VAT is not chargeable in airside shops on goods being sold to people leaving the country or the EU. Can anyone confirm that?
The duty on certain items like alcohol is another matter entirely, and as we know is deducted from items on which it is due for those leaving the EU.
Of course the big lie in "Duty-Free" shops is that many of the goods sold in them as "duty-free" are not subject to duty in the first place. If you ask the staff about this they are briefed to tell you the lie that VAT is actually "duty", and that "duty-free" really means "VAT-free".