I'm from the North East of England and eating nothing but French Fry sandwiches is not normal practice. I have had fried bread, but it is hardly the staple diet.
This discussion about healthy eating has been running here for many years. We do need to eat more fresh fruit and vegetables and there has been a '5-a-day' campaign running for several years. I'm not sure that just giving people fruit is the silver bullet. They have tried that in schools - giving every child a piece of fruit a day - but you can't force the child to eat it!
Schools meals were found to be made on 30p per day per meal (prisons spent twice as much) so these were made 'more healthy'. Did the children eat them? No, they bring in packed-lunches with sweets and chocolates, and parents hand in contraband food over the school gates.
There is a problem that cheap food is unhealthy food - lean meat costs more than fatty meat - chicken burgers made with mechanically removed leftovers are cheaper than breast - maybe a tax on the fat content of food would be a solution. I'm not sure on that one either - advertising of high fat content food to children has been banned, so cheese cannot be advertised anymore!!
Others point out that the cheapest food of all is fresh food cooked in the home and that what is needed is for people to start cooking at home. I think that is happening, but for many people the problem is one of time. The British also work longer hours on average than anyone else too.