Why are bread and pasta so popular and entrenched in our diets.

Habit and familiarity, satiety, availability, convenience, cost, the media, it's place in religion, literature.
These factors need to be addressed or at least kept in mind if we are to get the population at large to accept changes in these staples that will lead to better health.
Bread first.
Habit. This ensures that we buy the same thing over and over. We know where to put a hand on it almost automatically, and we have got used to pacing the rate at which we eat it to lock into our shopping schedules. All breads will have peculiarities and foibles - how it toasts, whether it is sliced and how it is wrapped - whether it stands up to the rigours of sandwich making and holding together as butter from the fridge is dragged over its surface, how long before it dries out and what can be done with it when it does.
Satiety. There is no doubt about it bread fills and does so quickly and provides by virtue of its refined carbohydrate content a quick fix - the one that keeps you going despite how little time you have to eat it.
Availability. Every corner shop will have some even if your supply from the supermarket or the bread shop ends.
Convenience. Bread is sliced and that is a big draw. The ability of bread to stay shapely after entering one of those slicing machines is pretty much a tweaking of components by the bakers in big bread factories but boutique bakers with their fancy loaves now will slice your loaf in front of you and even give you an option of thickness. Ever more choice from the big bakers means for instance you can get bread that is half 'brown' and half 'white'. It is very convenient to know that the loaf you have bought can be frozen and how convenient is is to take a slice or two from the loaf in the freezer and pop them in the toaster or microwave. Sandwiches are the tops in conveniently handing food. The hamburger shows this off remarkably well with a pile of wet and juicy components it is its own blotter and holder. And it is the form of sandwich that we can associate it with complementing almost any filling.
Cost. Bread is cheap if it is from the supermarkets own manufacturer and a little more pricey if from their on site bakery or a boutique bakery. End of the day and sell by sales sometimes results in almost give away prices. Despite the spectrum of prices especially those at the lower end bread makers are making a mint especially in the UK.
The media. This ruthlessly is used to exploit the bakers' wares, be it page sized adverts in the daily papers or kitchen scenes on the telly.
Its place in religion and literature. 'Bread is the staff of life' has biblical connotations and seems a phrase one has heard a thousand times.
Now pasta
Pretty much of the above could relate to pasta. Cheap filling and accommodating almost any meat, vegetable or sauce, and though not as convenient as bread is to the backbone of a sandwich, pasta is quick to prepare and easy to eat.
Bread and pasta are here to stay and this we cannot change so lets change that of which they are made:          Flour!!!!!!!!!!!!!!!