Completely relate!! We are packing for vacation right now. Too much of my suitcase is full of shelf-stable food and I'm trying to cut down on clothes to maximize the amount of food I can fit. Fingers crossed I don't get the same US customs officer as last time who threatened to deny my entry and cut up my passport for having an 'unreasonable' amount of food. Unfortunately, doctors cannot write notes saying you must bring food across the border due to food allergies, as there are legal restrictions on importing foods. Most officials accept food under 'medical supplies', when accompanied with documentation of food allergy, but not all. (This particular official was convinced I could easily find safe food in America.)
We pack food in all our suitcases, in case one gets lost. Having it all in the carry-ons isn't possible due the amount of other medical supplies (8 auto injectors, 3 inhalers, spacer, antihistamines, etc.) and a DSLR camera I wouldn't trust in checked baggage. (Not all airlines let me take on a bag of medical supplies in addition to the normal carry on.) I also bake a huge batch of muffins to take with us to eat something 'fresh' for a day or two, since home baked goods are allowed across the border - those go in carry on as well, along with as much fresh produce we can consume before the border crossing, if we have connecting flights.
Also, on vacation I eat to survive, and don't always enjoy it. Plain rice cooked in the hotel room microwave, mixed with some plain tinned beans and cut up vegetables isn't exactly appetizing, but it's safe. Especially when you're in a foreign country and don't know which brands have cross contamination, good labelling, etc. You can only eat so many instant oatmeal cups, bananas, and granola bars in two weeks. I wonder if I am allowed to bring some seasonings across the border: salt, pepper, herbs??
(I'm wishing we never booked vacation right now... planning food away from home, in another country, is very stressful. And half our trip will be at Disney! Even that is stressing me out, though I know it shouldn't.)