Also notice how in recent years there are less and less shops and eateries before security? Same thing. If pasengers spend longer in the departure lounge, they buy more stuff.
Er no
The whole point of removal of retail units pre security had to do with a realisation that a significant % of the trade in these stores were people who had no flights.
Adding people whose destination was the airport solely for shopping was seen as counter productive in they used up car parking spaces and generally made terminals busier than they needed to be.
Retailers found the business marginal hence why there was a significant turnover of retailers.
Elimination of this business allowed a significant increase in the space available for security control which caters to the people who really need to use the airport.