Anytime you make a choice between two non-consumable items based on weight, you are intrinsically making a base weight decision. Identifying that category is more useful than ignoring it. Here's why.
You can lose weight from your body (best option if not underweight), from consumables (food and water), or base weight. Next best place to lose weight is from base weight. If your food is dialed in, you'll have eaten everything by the end of the trip except emergency rations. So if you make a food choice that helps lose an ounce, whatever gets picked gets eaten before the end of trip and the savings ends. Base weight savings last the whole trip. If you're not thinking about base weight but you find your overall pack weight is too much, grabbing an apple out of your pack vs that extra shirt you don't need is the wrong choice to lower weight. As well, you can bring too much food but for newbies it's much more likely they'll bring too much gear and extra weight in the gear department will outpace extra food weight. Not to say don't consider food weight, cans are heavy right?
Base weight is a number that you achieve every hiking day and if it is a good number for you, you've minimized it, then you'll be happy every day. I do use a spreadsheet with weights of all my gear to calculate it. To think that somebody who does that is somehow unaware of their food and water weight is a faulty premise. If on the other hand, you've never done that, I think you might be in for a surprise or two about what you're carrying. And think about this, you can only carry so much but if you cut down some gear weight, that's more food for you to stay out even longer.