They probably didn’t have the population then that they do now. They have a crapload of people and not much land.
Thank y’all for the info-I guess the Brits will just have to encourage people to build more greenhouses, like people do in colder parts of the US, and learn to grow veggies at home-maybe start getting some flown in from Mexico and S America, too. Argentine and Chilean wines are very nice, reasonably priced, and even available here in BFE at the general store-so that might be better, if the Italians and French get all uppity-and there is always California...