Having had a quick look the kids pay more (£2.30) for their lunch than the PAYD rate.Brunch was a great idea in Germany, in England everyone went back home, 50 years ago most singlie soldiers couldn't afford to run a car, most have one today.
Pre packed lunches from my memory contained panda pops, churches crisps and the like, you simply cant make a premium brand lunch for a quid or so.
PAYD bought the Military into the 20th century (in the 21st century). Almost no other organisation has a similar system. Even with schools dinners you pay for what you eat, but the military struggled to make it work.