Didn't you know - airports are no longer provided for gaining access to flights, they are now shopping malls from which you can also fly if you can find the exit from the shopping mall part.
Personally I think airports should concentrate on being just that - yes passengers might like a drink or food prior to departure, or might like to buy a souvenire for whoever they are off to see, but that should be it.
If I want to go shopping then I will do it elsewhere, at normal (cheaper) prices and not in the airport.
Duty Free is just a name - whatever you buy from there is certainly available cheaper outside the airport even with duty added.
That will never happen though - passengers having a pleasant experience is secondary to making money via selling concessions to shops and retail outlets to operate on airport premises.