Campbell's Cream of Mushroom soup is used in the United States as a general utility food to help glue simple casseroles together.
For example: if you combine one can of Cream of Mushroom soup with one can of tuna and one bag of slightly firm egg noodles in a casserole dish, cover it with a crusty topping, and bake for 45 minutes at 350 degrees, you get a tuna noodle casserole.
Or you can take slice up 5 or 6 potatoes, and mix with a pound of cheese and a can of the aforementioned soup. Add the crust and bake as above and the result is Potatoes au Gratin.
The general rule is: a Starchy food + a flavor + one can CoM soup + a crust = a casserole. The condensed soup provides everything that is necessary to hold the casserole together and adds to the general creaminess. The crust can be a number of substances. My mother always used Italian breadcrumbs, but I have also seen crushed potato chips used for this purpose.
All these foods are simple enough for a bachelor but make enough food to feed a family. This makes Cream of Mushroom soup a good choice for the kitchen emergency shelf.