What they need is more people in the shops and car parks and FR are the ones who could do that for them!
I agree to an extent. When going off for a week or two in the sun, then I'd guess most would check-in luggage, freeing up hand baggage. However on recent flights with both Easyjet (to NCL) and Ryanair, the majority of weekenders have their clothes crammed into cabin sized trolley cases or back packs, with very little excess space for a shopping spree at the airport.
BHD staff, acting for FR, force passengers even with plastic bags from WH Smith, to put these goods into their cabin baggage or they wont travel!!! Even if its a newspaper and 500mls of water. I feel FR are particularly bad at this, tell the airport we'll get an extra x million through the doors every year, so provide us unsustainably low charges, and then employ incredibly strict hand baggage policies to discourage airport spend. Bars and food outlets may potentially benefit.