When I'm burning more than 5000 calories a day, I too eat anything I can get my hands on. It was me who tested the Pringles (plural) in the opened pack and I wasn't even particularly hungry!
Earlier in my backpacking career, I experienced getting run down after a couple of hard weeks, partly as a result of bad eating. I try always to get something really good into my rucksack these days, and then a bit of the stuff I would never touch at home doesn't really matter.
I do get concerned when hearing others laud food which is high in calories per gram. A balanced diet will keep a backpacker going longer. For example, protein is essential for repairing tired tissues, but isn't high in energy. However, if you need calories, fatty snacks, such as Pringles, really do the job. I've seen kids boil 50 ml of water with just one Cheerio (I think it was called). Boiling ruins the experiment, so these days I only let them set fire to half of one of these disgusting things. Loads of energy in all that fat.
My backpacking rarely includes desert, but in the environments I visit, replacing sodium chloride is all too easy. Maybe replacing salt is a valid reason in the desert, but it isn't in Britain.
There is also the psychology of backpacking nutrition. If you don't look forward to food, should you be carrying it? It seems to me that Pringles may pass two tests out of three and Meatloaf said that ain't bad.