We eat food/have sex for (among others) one or more of the following reasons: 1. fitness purposes (very roughly speaking, ensuring survival/reproduction), 2. hedonic purposes (very roughly speaking, relieving hunger/horniness), 3. eudaimonic purposes (very roughly speaking, enjoying great food/sex). Masturbation (incl. using dolls) only achieves 2, in-vitro fertilization only achieves 1 (well, actually 2 too when you gather the sperm to be used), and protected sex achieves 2 and 3 but not 1; with food the difference between 1 and 2 is less clear-cut, but IIUC foods with much more fructose than fibre can provide energy without really satiating you and vice versa, so we can say that eating dessert when you're not really hungry (and not trying to gain weight) achieves 3 but not 2. Soylent achieves 1 and 2, so it's kind-of analogous to masturbating and using the semen for IVF. But analogies are like ropes: if you pull them too far they will break down.

Do you only ever buy the cheapest available food that stops you being hungry and makes you feel satiated? Why or why not? Granted, some preferences may not be “hardwired”, but it doesn't make them any less real.